Статті в журналах: "Supernovae Ia distance scale"

1

Levin, S. F. "Cosmological distances scale: Pt. 11. Extraordinary evidences and cosmically jerk problem." Izmeritel`naya Tekhnika, no. 11 (2020): 3–8. http://dx.doi.org/10.32446/0368-1025it.2020-11-3-8.

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Statistical verification of the “extraordinary” evidence of “acceleration of the expansion of the Universe” due to the “cosmic push” at the redshift interval and at based on data on supernovae of type SN Ia, for which photometric distances were determined, was carried out. The transition from “deceleration” to “acceleration” is considered as a “breakdown” – a change in the structure and parameters of the model of the cosmological distance scale. It is shown that data from different sources do not form a compositionally homogeneous set. The scale model's “misalignment” (discord) was revealed for from a sample of 10 SN Ia obtained in the interval by the High-Z Supernovae Search Team, and for from a sample of 42 SN Ia obtained in the interval by the Supernovae Cosmology Project group. The reason for these “discrepancies” may be an unbalanced and random distribution of SN Ia over the observed range of redshifts with a clearly expressed non-metric character of the scale.

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2

Tammann, G. A. "The Cosmic Distance Scale." Symposium - International Astronomical Union 124 (1987): 151–85. http://dx.doi.org/10.1017/s0074180900159121.

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The zero-point of the extragalactic distance scale, defined by about two dozens of nearby, late-type galaxies, has remained nearly unchanged for the last decade, in spite of the advent of new techniques and great efforts. The distances are essentially tied to trigonometric parallax stars and hence independent of the Hyades modulus; they are consistent with RR Lyr stars. The mean zero-point is therefore probably secure to better than 10%.All known secondary distance indicators are still affected by zero-point errors, by problems in the definition of their relation between distance indicator and absolute magnitude (or linear size), and/or by selection bias. The effect of the very important selection bias (Malmquist effect), which causes a seemingly non-linear expansion field, is illustrated by two examples. To test for any true deviations from a linear expansion the Hubble diagram of nearly bias-free first-ranked cluster galaxies and supernovae Ia is shown; this imposes stringent limits on any non-linearity of the Hubble flow within v<5000 km s−1.After freeing the available distances of field galaxies from selection bias and after reducing them to a common zero-point, one finds HO=55–65. Several distance indicators require a best Virgo cluster modulus of (m-M)=31.60, which implies for the Coma cluster (m-M)=35.38 and, with v(Coma)=7217 km s−1, HO=60. Supernovae Ia and first-ranked cluster galaxies out to large distances give HO (global)=53. Thus the evidence from clusters and field galaxies is best satisfied by HO=55; the assigned mean error of ±7 is to indicate a 3σ range of 35<HO<75.Purely physical methods to determine extragalactic distances have modest weight yet; they will contribute eventually much to the determination of HO.If HO were as large as 100, several paradoxa would arise. The Milky Way would have a very high supernova frequency, our Galaxy and M31 would be oversized, the baryon density would fall short to bind clusters, and Friedman universes were excluded.Because all systematic errors have conspired and probably still conspire to measure HO too high, the true value could well be 40. Until new, decisive evidence becomes available, it is suggested for all practical purposes to use HO=50.

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3

Tammann, G. A., and B. Reindl. "Allan Sandage and the distance scale." Proceedings of the International Astronomical Union 8, S289 (August 2012): 13–25. http://dx.doi.org/10.1017/s1743921312021059.

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AbstractAllan Sandage returned to the distance scale and the calibration of the Hubble constant again and again during his active life, experimenting with different distance indicators. In 1952 his proof of the high luminosity of Cepheids confirmed Baade's revision of the distance scale (H0 ~ 250 km s−1 Mpc−1). During the next 25 years, he lowered the value to 75 and 55. Upon the arrival of the Hubble Space Telescope, he observed Cepheids to calibrate the mean luminosity of nearby Type Ia supernovae (SNe Ia) which, used as standard candles, led to the cosmic value of H0 = 62.3 ± 1.3 ± 5.0 km s−1 Mpc−1. Eventually he turned to the tip of the red giant branch (TRGB) as a very powerful distance indicator. A compilation of 176 TRGB distances yielded a mean, very local value of H0 = 62.9 ± 1.6 km s−1 Mpc−1 and shed light on the streaming velocities in the Local Supercluster. Moreover, TRGB distances are now available for six SNe Ia; if their mean luminosity is applied to distant SNe Ia, one obtains H0 = 64.6 ± 1.6 ± 2.0 km s−1 Mpc−1. The weighted mean of the two independent large-scale calibrations yields H0 = 64.1 km s−1 Mpc−1 within 3.6%.

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4

Sternberg, Assaf. "Evidence for Circumstellar Material in Type Ia Supernovae via Sodium Absorption Features." Proceedings of the International Astronomical Union 7, S281 (July 2011): 299–302. http://dx.doi.org/10.1017/s1743921312015232.

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AbstractType Ia supernovae are very good tools for measuring distances on a cosmic scale. The consensus view is that mass transfer onto a white dwarf in a close binary system leads to a thermonuclear explosion, though the nature of the mass donor is still uncertain. In the single-degenerate model it is a main-sequence star or an evolved star. In the double-degenerate model it is another white dwarf. We study the velocity structure of absorbing material along the line of sight to 35 Type Ia supernovae and find a statistical preference for blueshifted structures, likely arising in gas outflows from the supernova progenitor systems, consistent with a single-degenerate progenitor for a substantial fraction of Type Ia supernovae in nearby spiral galaxies.

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5

Levin, S. F. "Cosmological Distance Scale. Part 4. Calibration Based on SN Ia Supernovae." Measurement Techniques 58, no. 5 (August 2015): 477–84. http://dx.doi.org/10.1007/s11018-015-0740-0.

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6

Wong, Kenneth C., Sherry H. Suyu, Geoff C.-F. Chen, Cristian E. Rusu, Martin Millon, Dominique Sluse, Vivien Bonvin та ін. "H0LiCOW – XIII. A 2.4 per cent measurement of H0 from lensed quasars: 5.3σ tension between early- and late-Universe probes". Monthly Notices of the Royal Astronomical Society 498, № 1 (16 вересня 2019): 1420–39. http://dx.doi.org/10.1093/mnras/stz3094.

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ABSTRACT We present a measurement of the Hubble constant (H0) and other cosmological parameters from a joint analysis of six gravitationally lensed quasars with measured time delays. All lenses except the first are analysed blindly with respect to the cosmological parameters. In a flat Λ cold dark matter (ΛCDM) cosmology, we find $H_{0} = 73.3_{-1.8}^{+1.7}~\mathrm{km~s^{-1}~Mpc^{-1}}$, a $2.4{{\ \rm per\ cent}}$ precision measurement, in agreement with local measurements of H0 from type Ia supernovae calibrated by the distance ladder, but in 3.1σ tension with Planck observations of the cosmic microwave background (CMB). This method is completely independent of both the supernovae and CMB analyses. A combination of time-delay cosmography and the distance ladder results is in 5.3σ tension with Planck CMB determinations of H0 in flat ΛCDM. We compute Bayes factors to verify that all lenses give statistically consistent results, showing that we are not underestimating our uncertainties and are able to control our systematics. We explore extensions to flat ΛCDM using constraints from time-delay cosmography alone, as well as combinations with other cosmological probes, including CMB observations from Planck, baryon acoustic oscillations, and type Ia supernovae. Time-delay cosmography improves the precision of the other probes, demonstrating the strong complementarity. Allowing for spatial curvature does not resolve the tension with Planck. Using the distance constraints from time-delay cosmography to anchor the type Ia supernova distance scale, we reduce the sensitivity of our H0 inference to cosmological model assumptions. For six different cosmological models, our combined inference on H0 ranges from ∼73 to 78 km s−1 Mpc−1, which is consistent with the local distance ladder constraints.

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7

Tammann, G. A. "The Linearity of the Cosmic Expansion Field and the Value of the Hubble Constant." Symposium - International Astronomical Union 183 (1999): 31–47. http://dx.doi.org/10.1017/s0074180900132061.

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A linearity test shows H0 to decrease by 7% out to 18 000 km s–1. The value at 10 000 km s–1 is a good approximation to the mean value of H0 over very large scales. The construction of the extragalactic distance scale is discussed. Field galaxies, cluster distances relative to Virgo, and blue supernovae of type Ia yield H0 (cosmic) with increasing weight; they give consistently H0 = 57 ± 7 (external error). This value is supported by purely physical distance determinations (SZ effect, gravitational lenses, MWB fluctuations). Arguments for H0 > 70 are discussed and shown to be flawed.

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8

Lovyagin, Nikita Yu, Rustam I. Gainutdinov, Stanislav I. Shirokov, and Vladimir L. Gorokhov. "The Hubble Diagram: Jump from Supernovae to Gamma-ray Bursts." Universe 8, no. 7 (June 23, 2022): 344. http://dx.doi.org/10.3390/universe8070344.

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The Hubble diagram (HD) is a plot that contains a luminous distance modulus presented with respect to the redshift. The distance modulus–redshift relation of the most well-known “standard candles”, the type Ia supernovae (SN), is a crucial tool in cosmological model testing. In this work, we use the SN Ia data from the Pantheon catalogue to calibrate the Swift long gamma-ray bursts (LGRBs) as “standard candles” via the Amati relation. Thus, we expand the HD from supernovae to the area of the Swift LGRBs up to z∼8. To improve the quality of estimation of the parameters and their errors, we implement the Monte-Carlo uncertainty propagation method. We also compare the results of estimation of the Amati parameters calibrated by the SN Ia, and by the standard ΛCDM model and find no statistically significant distinction between them. Although the size of our LGRB sample is relatively small and the errors are high, we find this approach of expanding the cosmological distance scale promising for future cosmological tests.

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9

Levin, S. F. "Cosmological Distance Scale. Part 5. Metrological Expert Opinion on Type SN Ia Supernovae." Measurement Techniques 59, no. 8 (November 2016): 791–802. http://dx.doi.org/10.1007/s11018-016-1047-5.

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10

Regős, Enikő. "Progenitor Evolution and Dark Energy Time Variation from CLASH SNe Ia." Proceedings of the International Astronomical Union 7, S281 (July 2011): 26–28. http://dx.doi.org/10.1017/s1743921312014627.

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AbstractThe nature and timescales behind the growth of the white dwarf toward the Chandrasekhar mass are not known. The two leading competing scenarios for Type Ia supernovae (SNe Ia) are accretion from a companion [single degenerate (SD)] or merger with another white dwarf [double degenerate (DD)]. Measurement of the SNe Ia delay time distribution could distinguish between these scenarios. Possibly both channels operate, on short (SD) and long (DD) time scales. A supernova search in parallel with our Cluster Lensing And Supernova survey with Hubble extends the Hubble diagram of SNe Ia to z > 1.5, probing progenitor evolution and testing the constancy of dark energy (DE) with time. We use HST ACS to detect SNe Ia at 1 < z < 1.5 and WFC3 to find SNe Ia at 1.5 < z < 2.5, thus providing constraints for the variation in the DE equation of state. This redshift epoch provides the unique chance to test SNe Ia distance measurements for the deleterious effects of evolution independent of our ignorance of dark energy. Our program provides the first measurement of the SNe Ia rate at z ~ 2.

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11

Levin, S. F. "Cosmological distances scale. Pt. 12. Confluence analysis, rang inversion and tests for inadequacy." Izmeritel`naya Tekhnika, no. 12 (2020): 13–21. http://dx.doi.org/10.32446/0368-1025it.2020-12-13-21.

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The measurement problem of calibration of the cosmological distance scale is considered from the point of view of the conditions of applicability of the regression analysis. It is shown that the rank inversion and statistical heterogeneity of data on supernovae SN Ia, which were used in 1998–1999 to detect the “acceleration of the expansion of the Universe”, and in 2004–2007 – as “extraordinary evidence” of its existence, is the reason for the discrepancy and inconsistency of the obtained estimates of the parameters of the Friedman-Robertson-Walker model. Although the use of tests for inadequacy for models of the cosmological distance scale reduces these negative effects, the fact remains that the cosmological distance scale based on redshift has neither the status of metric nor ordinal.

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12

Lu, Jia, Lifan Wang, Xingzhuo Chen, David Rubin, Saul Perlmutter, Dietrich Baade, Jeremy Mould, Jozsef Vinko, Enikő Regős, and Anton M. Koekemoer. "Constraints on Cosmological Parameters with a Sample of Type Ia Supernovae from JWST." Astrophysical Journal 941, no. 1 (December 1, 2022): 71. http://dx.doi.org/10.3847/1538-4357/ac9f49.

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Abstract We investigate the potential of using a sample of very high-redshift (2 ≲ z ≲ 6) (VHZ) Type Ia supernovae (SNe Ia) attainable by JWST on constraining cosmological parameters. At such high redshifts, the age of the universe is young enough that the VHZ SN Ia sample comprises the very first SNe Ia of the universe, with progenitors among the very first generation of low-mass stars that the universe has made. We show that the VHZ SNe Ia can be used to disentangle systematic effects due to the luminosity distance evolution with redshifts intrinsic to SN Ia standardization. Assuming that the systematic evolution can be described by a linear or logarithmic formula, we found that the coefficients of this dependence can be determined accurately and decoupled from cosmological models. Systematic evolution as large as 0.15 mag and 0.45 mag out to z = 5 can be robustly separated from popular cosmological models for linear and logarithmic evolution, respectively. The VHZ SNe Ia will lay the foundation for quantifying the systematic redshift evolution of SN Ia luminosity distance scales. When combined with SN Ia surveys at comparatively lower redshifts, the VHZ SNe Ia allow for the precise measurement of the history of the expansion of the universe from z ∼ 0 to the epoch approaching reionization.

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13

Anderson, Richard I. "Towards a 1% measurement of the Hubble constant: accounting for time dilation in variable-star light curves." Astronomy & Astrophysics 631 (November 2019): A165. http://dx.doi.org/10.1051/0004-6361/201936585.

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Assessing the significance and implications of the recently established Hubble tension requires the comprehensive identification, quantification, and mitigation of uncertainties and/or biases affecting H0 measurements. Here, we investigate the previously overlooked distance scale bias resulting from the interplay between redshift and Leavitt laws in an expanding Universe: Redshift-Leavitt bias (RLB). Redshift dilates oscillation periods of pulsating stars residing in supernova-host galaxies relative to periods of identical stars residing in nearby (anchor) galaxies. Multiplying dilated log P with Leavitt Law slopes leads to underestimated absolute magnitudes, overestimated distance moduli, and a systematic error on H0. Emulating the SH0ES distance ladder, we estimate an associated H0 bias of (0.27 ± 0.01)% and obtain a corrected H0 = 73.70 ± 1.40 km s−1 Mpc−1. RLB becomes increasingly relevant as distance ladder calibrations pursue greater numbers of ever more distant galaxies hosting both Cepheids (or Miras) and type-Ia supernovae. The measured periods of oscillating stars can readily be corrected for heliocentric redshift (e.g. of their host galaxies) in order to ensure H0 measurements free of RLB.

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14

Zhang, Pengfei, and Xinhe Meng. "SNe data analysis in variable speed of light cosmologies without cosmological constant." Modern Physics Letters A 29, no. 24 (August 7, 2014): 1450103. http://dx.doi.org/10.1142/s021773231450103x.

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In this work, we aim to show the possibilities of the variable speed of light (VSL) theory in explaining the type Ia supernovae (SNe) observations without introducing dark energy. The speed of light is assumed to be scale factor-dependent, which is the most popular assumption in VSL theory. We show the modified calculation of the distance modulus and the validity of the redshift-scale factor relation in VSL theory. Three different models of VSL are tested SNe data-sets with proper constraints on the model parameters. The comparison of the three models and flat ΛCDM in distance modulus is showed. Some basic problems and the difficulties of the confirmation of the VSL theory are also discussed.

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15

Toonen, Silvia, Gijs Nelemans, and Simon Portegies Zwart. "Double White Dwarf Merger Rates." Proceedings of the International Astronomical Union 7, S281 (July 2011): 223–24. http://dx.doi.org/10.1017/s1743921312015086.

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AbstractType Ia supernovae (SNe Ia) are very successfully used as standard candles on cosmological distance scales, but so far the nature of the progenitor(s) is unclear. A possible scenario for SNe Ia are merging carbon/oxygen white dwarfs with a combined mass exceeding the Chandrasekhar mass. We determine the theoretical rates and delay time distribution of these mergers for two different common envelope prescriptions and metallicities. The shape of the delay time distributions is rather insensitive to the assumptions. The normalization is a factor ~3–13 too low compared to observations.

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16

Dhawan, S., A. Goobar, M. Smith, J. Johansson, M. Rigault, J. Nordin, R. Biswas, et al. "The Zwicky Transient Facility Type Ia supernova survey: first data release and results." Monthly Notices of the Royal Astronomical Society 510, no. 2 (November 11, 2021): 2228–41. http://dx.doi.org/10.1093/mnras/stab3093.

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ABSTRACT Type Ia supernovae (SNe Ia) in the nearby Hubble flow are excellent distance indicators in cosmology. The Zwicky Transient Facility (ZTF) has observed a large sample of SNe from an untargeted, rolling survey, reaching 20.8, 20.6, and 20.3 mag in g r, and i band, respectively. With an FoV of 47 deg2, ZTF discovered > 3000 SNe Ia in a little over 2.5 yr. Here, we report on the sample of 761 spectroscopically classified SNe Ia from the first year of operations (DR1). The sample has a median redshift $\bar{z} =$ 0.057, nearly a factor of 2 higher than the current low-z sample. Our sample has a total of 934 spectra, of which 632 were obtained with the robotic SEDm on Palomar P60. We assess the potential for precision cosmology for a total of 305 SNe with redshifts from host galaxy spectra. The sample is already comparable in size to the entire combined literature low-z anchor sample. The median first detection is 13.5 d before maximum light, about 10 d earlier than the median in the literature. Furthermore, six SNe from our sample are at DL < 80 Mpc, for which host galaxy distances can be obtained in the JAMES WEBB SPACE TELESCOPE era, such that we have calibrator and Hubble flow SNe observed with the same instrument. In the entire duration of ZTF-I, we have observed nearly 50 SNe for which we can obtain calibrator distances, key for per cent level distance scale measurements.

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17

Pierce, Michael J. "Luminosity-line-width relations and the extragalactic distance scale. 2: A comparison with Types IA and II supernovae." Astrophysical Journal 430 (July 1994): 53. http://dx.doi.org/10.1086/174381.

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18

Freedman, Wendy L., Jeremy R. Mould, Robert C. Kennicutt, and Barry F. Madore. "The Hubble Space Telescope Key Project to Measure the Hubble Constant." Symposium - International Astronomical Union 183 (1999): 17–30. http://dx.doi.org/10.1017/s007418090013205x.

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A Joint Discussion on the extragalactic distance scale and the Hubble constant took place fifteen years ago, at the 1982 XVIIIth General Assembly of the IAU, held in Patras, Greece. At that time, the newest applications of infrared photometers to Tully-Fisher measurements (Aaronson 1983) and Cepheid distances (Madore 1983) were reported. CCDs were just coming into use and had not yet been applied to extragalactic distance determinations; all of the extragalactic Cepheid distances were based on photographic Argelander (eye-estimated) photometry (Tammann and Sandage 1983 and references therein). No Cepheid distances to type Ia supernova-host galaxies were available.

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19

Peterson, Erik R., W. D’Arcy Kenworthy, Daniel Scolnic, Adam G. Riess, Dillon Brout, Anthony Carr, Hélène Courtois, et al. "The Pantheon+ Analysis: Evaluating Peculiar Velocity Corrections in Cosmological Analyses with Nearby Type Ia Supernovae." Astrophysical Journal 938, no. 2 (October 1, 2022): 112. http://dx.doi.org/10.3847/1538-4357/ac4698.

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Abstract Separating the components of redshift due to expansion and peculiar motion in the nearby universe (z < 0.1) is critical for using Type Ia Supernovae (SNe Ia) to measure the Hubble constant (H 0) and the equation-of-state parameter of dark energy (w). Here, we study the two dominant “motions” contributing to nearby peculiar velocities: large-scale, coherent-flow (CF) motions and small-scale motions due to gravitationally associated galaxies deemed to be in a galaxy group. We use a set of 584 low-z SNe from the Pantheon+ sample, and evaluate the efficacy of corrections to these motions by measuring the improvement of SN distance residuals. We study multiple methods for modeling the large and small-scale motions and show that, while group assignments and CF corrections individually contribute to small improvements in Hubble residual scatter, the greatest improvement comes from the combination of the two (relative standard deviation of the Hubble residuals, Rel. SD, improves from 0.167 to 0.157 mag). We find the optimal flow corrections derived from various local density maps significantly reduce Hubble residuals while raising H 0 by ∼0.4 km s−1 Mpc−1 as compared to using CMB redshifts, disfavoring the hypothesis that unrecognized local structure could resolve the Hubble tension. We estimate that the systematic uncertainties in cosmological parameters after optimally correcting redshifts are 0.06–0.11 km s−1 Mpc−1 in H 0 and 0.02–0.03 in w which are smaller than the statistical uncertainties for these measurements: 1.5 km s−1 Mpc−1 for H 0 and 0.04 for w.

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20

Boruah, Supranta S., Michael J. Hudson, and Guilhem Lavaux. "Cosmic flows in the nearby Universe: new peculiar velocities from SNe and cosmological constraints." Monthly Notices of the Royal Astronomical Society 498, no. 2 (August 20, 2020): 2703–18. http://dx.doi.org/10.1093/mnras/staa2485.

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ABSTRACT The peculiar velocity field offers a unique way to probe dark matter density field on large scales at low redshifts. In this work, we have compiled a new sample of 465 peculiar velocities from low redshift ($z$ < 0.067) Type Ia supernovae. We compare the reconstructed velocity field derived from the 2M++ galaxy redshift compilation to the supernovae, the SFI++ and the 2MTF Tully–Fisher distance catalogues. We used a forward method to jointly infer the distances and the velocities of distance indicators by comparing the observations to the reconstruction. Comparison of the reconstructed peculiar velocity fields to observations allows us to infer the cosmological parameter combination fσ8, and the bulk flow velocity arising from outside the survey volume. The residual bulk flow arising from outside the 2M++ volume is inferred to be $171^{+11}_{-11}$ km s−1 in the direction l = 301° ± 4° and b = 0° ± 3°. We obtain fσ8 = 0.400 ± 0.017, equivalent to S8 ≈ σ8(Ωm/0.3)0.55 = 0.776 ± 0.033, which corresponds to an approximately $4{{\ \rm per\ cent}}\,$ statistical uncertainty on the value of fσ8. Our inferred value is consistent with other low redshift results in the literature.

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21

Ciardullo, Robin. "The planetary nebula luminosity function." Proceedings of the International Astronomical Union 8, S289 (August 2012): 247–54. http://dx.doi.org/10.1017/s1743921312021503.

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AbstractAlthough the method has no theoretical explanation, the [Oiii]λ5007Å planetary nebula luminosity function (PNLF) is an extremely valuable tool for obtaining accurate (< 10%) extragalactic distances out to ~ 18 Mpc. Because the PNLF works in large galaxies of all Hubble types, it is one of the best tools we have for cross-checking the results of other methods and identifying systematic offsets between the Population I and Population II distance ladders. We review the PNLF's calibration and show that the method's Cepheid-derived zero point is virtually identical to that inferred from measurements of the tip of the red giant branch. We then compare the PNLF to the surface brightness fluctuations method and demonstrate that the latter's calibration yields a distance scale that is ~ 15% larger than that of the PNLF. We argue that this offset is likely due to a number of factors, including the effects of reddening on both of the techniques. We conclude by discussing the use of the PNLF for supernovae Type Ia calibration and considering the outstanding problems associated with the method.

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22

Chen, Geoff C. F., Christopher D. Fassnacht, Sherry H. Suyu, Akın Yıldırım, Eiichiro Komatsu, and José Luis Bernal. "TDCOSMO." Astronomy & Astrophysics 652 (July 30, 2021): A7. http://dx.doi.org/10.1051/0004-6361/202039895.

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Time-delay cosmography with gravitationally lensed quasars plays an important role in anchoring the absolute distance scale and hence measuring the Hubble constant, H0, independent of traditional distance ladder methodology. A current potential limitation of time-delay distance measurements is the mass-sheet transformation (MST), which leaves the lensed imaging unchanged but changes the distance measurements and the derived value of H0. In this work we show that the standard method of addressing the MST in time-delay cosmography, through a combination of high-resolution imaging and the measurement of the stellar velocity dispersion of the lensing galaxy, depends on the assumption that the ratio, Ds/Dds, of angular diameter distances to the background quasar and between the lensing galaxy and the quasar can be constrained. This is typically achieved through the assumption of a particular cosmological model. Previous work (TDCOSMO IV) addressed the mass-sheet degeneracy and derived H0 under the assumption of the ΛCDM model. In this paper we show that the mass-sheet degeneracy can be broken without relying on a specific cosmological model by combining lensing with relative distance indicators such as supernovae Type Ia and baryon acoustic oscillations, which constrain the shape of the expansion history and hence Ds/Dds. With this approach, we demonstrate that the mass-sheet degeneracy can be constrained in a cosmological model-independent way. Hence model-independent distance measurements in time-delay cosmography under MSTs can be obtained.

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23

Sedgwick, Thomas M., Chris A. Collins, Ivan K. Baldry, and Philip A. James. "The effects of peculiar velocities in SN Ia environments on the local H0 measurement." Monthly Notices of the Royal Astronomical Society 500, no. 3 (November 7, 2020): 3728–42. http://dx.doi.org/10.1093/mnras/staa3456.

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ABSTRACT The discrepancy between estimates of the Hubble constant (H0) measured from local (z ≲ 0.1) scales and from scales of the sound horizon is a crucial problem in modern cosmology. Peculiar velocities (vpec) of standard candle distance indicators can systematically affect local H0 measurements. We here use 2MRS galaxies to measure the local galaxy density field, finding a notable z < 0.05 underdensity in the SGC-6dFGS region of 27 ± 2 per cent. However, no strong evidence for a ‘Local Void’ pertaining to the full 2MRS sky coverage is found. Galaxy densities are used to measure a density parameter, Δϕ+−, which we introduce as a proxy for vpec that quantifies density gradients along a supernova (SN) line of sight. Δϕ+− is found to correlate with local H0 estimates from 88 Pantheon Type Ia supernovae (SNe Ia; 0.02 < z < 0.05). Density structures on scales of ∼50 Mpc are found to correlate strongest with H0 estimates in both the observational data and in mock data from the MDPL2-Galacticus simulation. Using trends of H0 with Δϕ+−, we can correct for the effects of density structure on local H0 estimates, even in the presence of biased vpec. However, the difference in the inferred H0 estimate with and without the peculiar velocity correction is limited to < 0.1 per cent. We conclude that accounting for environmentally induced peculiar velocities of SN Ia host galaxies does not resolve the tension between local and CMB-derived H0 estimates.

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24

Wagner, Jenny, and Sven Meyer. "Generalized model-independent characterization of strong gravitational lenses V: reconstructing the lensing distance ratio by supernovae for a general Friedmann universe." Monthly Notices of the Royal Astronomical Society 490, no. 2 (September 30, 2019): 1913–27. http://dx.doi.org/10.1093/mnras/stz2717.

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ABSTRACT We determine the cosmic expansion rate from supernovae of type Ia to set up a data-based distance measure that does not make assumptions about the constituents of the universe, i.e. about a specific parametrization of a Friedmann cosmological model. The scale, determined by the Hubble constant H0, is the only free cosmological parameter left in the gravitational lensing formalism. We investigate to which accuracy and precision the lensing distance ratio D is determined from the Pantheon sample. Inserting D and its uncertainty into the lensing equations for given H0, especially the time-delay equation between a pair of multiple images, allows to determine lens properties, especially differences in the lensing potential (Δϕ), without specifying a cosmological model. We expand the luminosity distances into an analytic orthonormal basis, determine the maximum-likelihood weights for the basis functions by a globally optimal χ2-parameter estimation, and derive confidence bounds by Monte Carlo simulations. For typical strong lensing configurations between z = 0.5 and 1.0, Δϕ can be determined with a relative imprecision of 1.7 per cent, assuming imprecisions of the time delay and the redshift of the lens on the order of 1 per cent. With only a small, tolerable loss in precision, the model-independent lens characterisation developed in this paper series can be generalised by dropping the specific Friedmann model to determine D in favour of a data-based distance ratio. Moreover, for any astrophysical application, the approach presented here, provides distance measures for z ≤ 2.3 that are valid in any homogeneous, isotropic universe with general relativity as theory of gravity.

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25

Levin, Sergey F. "Cosmological distances scale. Part 13: galactic polar redshift anisotropy of quasars and supernovae of type SN Ia." Izmeritel`naya Tekhnika, no. 10 (2022): 11–18. http://dx.doi.org/10.32446/0368-1025it.2022-10-11-18.

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26

Mohayaee, Roya, Mohamed Rameez, and Subir Sarkar. "Do supernovae indicate an accelerating universe?" European Physical Journal Special Topics 230, no. 9 (June 23, 2021): 2067–76. http://dx.doi.org/10.1140/epjs/s11734-021-00199-6.

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AbstractIn the late 1990’s, observations of two directionally-skewed samples of, in total, 93 Type Ia supernovae were analysed in the framework of the Friedmann–Lemaître–Robertson–Walker (FLRW) cosmology. Assuming these to be ‘standard(isable) candles’ it was inferred that the Hubble expansion rate is accelerating as if driven by a positive Cosmological Constant $$\varLambda $$ Λ in Einstein’s theory of gravity. This is still the only direct evidence for the ‘dark energy’ that is the dominant component of today’s standard $$\varLambda $$ Λ CDM cosmological model. Other data such as baryon acoustic oscillations (BAO) in the large-scale distribution of galaxies, temperature fluctuations in the cosmic microwave background (CMB), measurement of stellar ages, the rate of growth of structure, etc are all ‘concordant’ with this model but do not provide independent evidence for accelerated expansion. The recent discussions about whether the inferred acceleration is real rests on analysis of a larger sample of 740 SNe Ia which shows that these are not quite standard candles, and more importantly highlights the ‘corrections’ that are applied to analyse the data in the FLRW framework. The latter holds in the reference frame in which the CMB is isotropic, whereas observations are carried out in our heliocentric frame in which the CMB has a large dipole anisotropy. This is assumed to be of kinematic origin i.e. due to our non-Hubble motion driven by local inhomogeneity in the matter distribution which has grown under gravity from primordial density perturbations traced by the CMB fluctuations. The $$\varLambda $$ Λ CDM model predicts how this peculiar velocity should fall off as the averaging scale is raised and the universe becomes sensibly homogeneous. However observations of the local ‘bulk flow’ are inconsistent with this expectation and convergence to the CMB frame is not seen. Moreover, the kinematic interpretation implies a corresponding dipole in the sky distribution of high redshift quasars, which is rejected by observations at $$4.9\sigma $$ 4.9 σ . Hence the peculiar velocity corrections employed in supernova cosmology are inconsistent and discontinuous within the data. The acceleration of the Hubble expansion rate is in fact anisotropic at $$3.9\sigma $$ 3.9 σ and aligned with the bulk flow. Thus dark energy could be an artefact of analysing data assuming that we are idealised observers in an FLRW universe, when in fact the real universe is inhomogeneous and anisotropic out to distances large enough to impact on cosmological analyses.

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27

RADICELLA, NINFA, MAURO SERENO, and ANGELO TARTAGLIA. "COSMOLOGICAL CONSTRAINTS FOR THE COSMIC DEFECT THEORY." International Journal of Modern Physics D 20, no. 06 (June 5, 2011): 1039–51. http://dx.doi.org/10.1142/s0218271811019268.

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The cosmic defect theory has been confronted with four observational constraints: primordial nuclear species abundances emerging from the big bang nucleosynthesis; large scale structure formation in the Universe; cosmic microwave background acoustic scale; luminosity distances of type Ia supernovae. The test has been based on a statistical analysis of the a posteriori probabilities for three parameters of the theory. The result has been quite satisfactory and such that the performance of the theory is not distinguishable from that of the ΛCDM theory. The use of the optimal values of the parameters for the calculation of the Hubble constant and the age of the Universe confirms the compatibility of the cosmic defect approach with observations.

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28

Gibson, Brad K., Peter B. Stetson, Wendy L. Freedman, Jeremy R. Mould, Robert C. Kennicutt, Jr., John P. Huchra, Shoko Sakai, et al. "TheHubble Space TelescopeKey Project on the Extragalactic Distance Scale. XXV. A Recalibration of Cepheid Distances to Type Ia Supernovae and the Value of the Hubble Constant." Astrophysical Journal 529, no. 2 (February 2000): 723–44. http://dx.doi.org/10.1086/308306.

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29

Hartman, S. T. H., H. A. Winther, and D. F. Mota. "Constraints on self-interacting Bose-Einstein condensate dark matter using large-scale observables." Journal of Cosmology and Astroparticle Physics 2022, no. 02 (February 1, 2022): 005. http://dx.doi.org/10.1088/1475-7516/2022/02/005.

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Abstract Constraints on the cosmic history of self-interacting Bose-Einstein condensed (SIBEC) dark matter (DM) are obtained using the cosmic microwave background (CMB), baryonic acoustic oscillations (BAO), growth factor measurements, and type Ia supernovae (SNIa) distances. Four scenarios are considered, one with purely SIBEC-DM, and three in which SIBEC-DM is the final product of some transition from different initial states, which are either cold, warm, or has a constant equation of state. Using a fluid approximation for the self-interacting scalar field it is found that in the simplest scenario of purely SIBEC-DM the self-interaction necessary for solving the cusp-core problem, with core-radii of low-mass halos of order R c ≳ 1kpc, is excluded at 2.4σ, or 98.5% confidence. Introducing a transition, however, relaxes this constraint, but the transitions are preferred to be after matter-radiation equality, and the initial phase to be cold.

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30

Levin, S. F. "Measurement problem of structural-parametric identification on supernovae type SN Ia for cosmological distances scale of red shift based." Physical Interpretation of Relativity Theory: Proceedings of International Meeting., no. 1 (December 2015): 299–310. http://dx.doi.org/10.18698/2309-7604-2015-1-299-310.

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31

Raikov, A. A., V. V. Orlov, and R. V. Gerasim. "Determination of the Fractal Dimensionality of Large-Scale Structure With Type Ia Supernovae by the Method of Pairwise Distances." Astrophysics 57, no. 2 (June 2014): 287–95. http://dx.doi.org/10.1007/s10511-014-9334-9.

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32

Varieschi, Gabriele U. "Kinematical Conformal Cosmology: Fundamental Parameters from Astrophysical Observations." ISRN Astronomy and Astrophysics 2011 (August 17, 2011): 1–24. http://dx.doi.org/10.5402/2011/806549.

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We continue the presentation of an alternative cosmology based on conformal gravity, following our kinematical approach to the subject introduced in a recent paper. In line with the assumptions of our model, which proposes a closed-form expression for the cosmic scale factor , we revise the Hubble and deceleration parameters and introduce modified cosmological distances, analyzing in particular the case of the luminosity distance. Our kinematical conformal cosmology is then able to explain the anomalous acceleration of the Pioneer spacecraft, as due to a local region of gravitational blueshift. From the reported data of the Pioneer anomaly, we also compute the current value of our first fundamental parameter, , in line with the original estimate by P. Mannheim of this quantity. Our second fundamental parameter, , interpreted as the current value of a cosmological time variable, is derived from a detailed fitting of type Ia supernovae “gold-silver” data, producing Hubble plots of the same quality of those obtained by standard cosmology, but without requiring any dark matter or dark energy contribution. If further experiments will confirm the presence of an anomalous frequency blueshift in the outer region of the solar system, as described by our model, kinematical conformal cosmology might become a viable alternative to standard cosmological theories.

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33

Pradhan, Anirudh, Priyanka Garg, and Archana Dixit. "FRW cosmological models with cosmological constant in f(R, T) theory of gravity." Canadian Journal of Physics 99, no. 9 (September 2021): 741–53. http://dx.doi.org/10.1139/cjp-2020-0282.

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In the present paper, we have generalized the behaviors of the transit-decelerating to accelerating FRW cosmological model in f(R, T) gravity theory, where R and T are Ricci scalar and trace of the energy–momentum tensor, respectively. The solution of the corresponding field equations is obtained by assuming a linear function of the Hubble parameter H (i.e., q = c1 + c2H), which gives a time-dependent deceleration parameter [Formula: see text], where c3 and c2 are arbitrary integrating constants (Tiwari et al. Eur. Phys. J. Plus, 131, 447 (2016); Ibid. 132, 126 (2017)). There are two scenarios in which we explain the particular form of scale factor thus obtained: (i) by using the recent constraints from observational Hubble data (OHD) and joint light curves (JLA) data, which show a cosmic deceleration to acceleration and (ii) by using new constraints from supernovae type Ia union data, which show accelerating expansion of the universe (q < 0) throughout its evolution. We have observed that EoS parameter, energy density parameters, and important cosmological planes yield results compatible with the modern observational data. For the derived models, we have calculated various physical parameters as luminosity distance, distance modulus, and apparent magnitude versus redshift for both current supporting observations.

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34

Zhou, Zhihuan, Gang Liu, Yuhao Mu, and Lixin Xu. "Can phantom transition at z ∼ 1 restore the Cosmic concordance?" Monthly Notices of the Royal Astronomical Society 511, no. 1 (January 10, 2022): 595–606. http://dx.doi.org/10.1093/mnras/stac053.

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ABSTRACT The tension among inferences of Hubble constant (H0) is found in a large array of data sets combinations. Modification to the late expansion history is the most direct solution to this discrepancy. In this work, we examine the viability of restoring the cosmological concordance with a novel version of transitional dark energy (TDE). The main anchors for the cosmic distance scale: cosmic microwave background (CMB) radiation, baryon acoustic oscillation (BAO), and Type Ia supernova (SNe Ia) calibrated by Cepheids form a ‘impossible trinity’, i.e. it’s plausible to reconcile with any two of the three but unlikely to accommodate them all. Particularly, the tension between BAO and the calibrated SNe Ia cannot be reconciled within the scenarios of late dark energy. Nevertheless, our analysis suggests that the TDE model can reconcile with CMB and SNe Ia calibrated by its absolute magnitude (MB) when the equation of state (EoS) of DE transits around z ∼ 1. Meanwhile, we see a positive sign that the EoS transits with the inclusion of a local prior on MB, whereas the opposite is true without the MB prior.

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35

Gupta, Rajendra P. "Constraining Coupling Constants’ Variation with Supernovae, Quasars, and GRBs." Symmetry 15, no. 2 (January 17, 2023): 259. http://dx.doi.org/10.3390/sym15020259.

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Dirac, in 1937, proposed the potential variation of coupling constants derived from his large numbers hypothesis. Efforts have continued since then to constrain their variation by various methods, including astrophysical and cosmological observations. We briefly discuss several methods used for the purpose while focusing primarily on the use of supernovae type 1a, quasars, and gamma-ray bursts as cosmological probes for determining cosmological distances. Supernovae type Ia (SNeIa) are considered the best standard candles since their intrinsic luminosity can be determined precisely from their light curves. However, they have only been observed up to about redshift z = 2.3, mostly at z ≤ 1.5. Quasars are the brightest non-transient cosmic sources in the Universe. They have been observed up to z = 7.5. Certain types of quasars can be calibrated well enough for their use as standard candles but with a higher degree of uncertainty in their intrinsic luminosity than SNeIa. Gamma-ray bursts (GRBs) are even brighter than quasars, and they have been observed up to z = 9.4. They are sources of highly transient radiation lasting from tens of milliseconds to several minutes and, in rare cases, a few hours. However, they are even more challenging to calibrate as standard candles than quasars. Both quasars and GRBs use SNeIa for distance calibration. What if the standard candles’ intrinsic luminosities are affected when the coupling constants become dynamic and depend on measured distances? Assuming it to be constant at all cosmic distances leads to the wrong constraint on the data-fitted model parameters. This paper uses our earlier finding that the speed of light c, the gravitational constant G, the Planck constant h, and the Boltzmann constant k vary in such a way that their variation is interrelated as ${G \sim c^{3} \sim h^{3} \sim k^{3/2}}$ with ${\overset{.}{G}/G = 3\overset{.}{c}/c = 3\overset{.}{h}/h = 1.5\overset{.}{k}/k}$ = 3.90(±0.04) × ${10^{-10}}$ yr${^{-1}}$ and corroborates it with SNeIa, quasars, and GRBs observational data. Additionally, we show that this covarying coupling constant model may be better than the standard ${\Lambda}$CDM model for using quasars and GRBs as standard candles and predict that the mass of the GRBs scales with z as ${((1+z)^{1/3}-1)}$. Noether’s symmetry on the coupling constants is now transferred effectively to the constant in the function relating to their variation.

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36

Wei, Jun-Jie, Yun Chen, Shuo Cao, and Xue-Feng Wu. "Direct Estimate of the Post-Newtonian Parameter and Cosmic Curvature from Galaxy-scale Strong Gravitational Lensing." Astrophysical Journal Letters 927, no. 1 (February 28, 2022): L1. http://dx.doi.org/10.3847/2041-8213/ac551e.

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Abstract Einstein’s theory of general relativity (GR) has been precisely tested on solar system scales, but extragalactic tests are still poorly performed. In this work, we use a newly compiled sample of galaxy-scale strong gravitational lenses to test the validity of GR on kiloparsec scales. In order to solve the circularity problem caused by the presumption of a specific cosmological model based on GR, we employ the distance sum rule in the Friedmann–Lemaître–Robertson–Walker metric to directly estimate the parameterized post-Newtonian (PPN) parameter γ PPN and the cosmic curvature Ω k by combining observations of strong lensing and Type Ia supernovae. This is the first simultaneous measurement of γ PPN and Ω k without any assumptions about the contents of the universe or the theory of gravity. Our results show that γ PPN = 1.11 − 0.09 + 0.11 and Ω k = 0.48 − 0.71 + 1.09 , indicating a strong degeneracy between the two quantities. The measured γ PPN, which is consistent with the prediction of 1 from GR, provides a precise extragalactic test of GR with a fractional accuracy better than 9.0%. If a prior of the spatial flatness (i.e., Ω k = 0) is adopted, the PPN parameter constraint can be further improved to γ PPN = 1.07 − 0.07 + 0.07 , representing a precision of 6.5%. On the other hand, in the framework of GR (i.e., γ PPN = 1), our results are still marginally compatible with zero curvature ( Ω k = − 0.12 − 0.36 + 0.48 ), supporting no significant deviation from a flat universe.

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37

Shimon, Meir. "Possible resolution of the Hubble tension with Weyl invariant gravity." Journal of Cosmology and Astroparticle Physics 2022, no. 04 (April 1, 2022): 048. http://dx.doi.org/10.1088/1475-7516/2022/04/048.

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Abstract We explore cosmological implications of a genuinely Weyl invariant (WI) gravitational interaction. The latter reduces to general relativity in a particular conformal frame for which the gravitational coupling and active gravitational masses are fixed. Specifically, we consider a cosmological model in this framework that is dynamically identical to the standard model (SM) of cosmology. However, kinematics of test particles traveling in the new background metric is modified thanks to a new (cosmological) fundamental mass scale, γ, of the model that emerges as an integration constant of the classical field equations. Since the lapse-function of the new metric is radially-dependent any incoming photon experiences (gravitational) red/blueshift in the comoving frame, unlike in the SM. Distance scales are modified as well due to the scale γ. The claimed 4.4σ tension level between the locally measured Hubble constant, H 0, with SH0ES and the corresponding value inferred from the cosmic microwave background (CMB) could then be significantly alleviated by an earlier-than-thought recombination. Assuming vanishing spatial curvature, either one of the Planck 2018 (P18) or dark energy survey (DES) yr1 data sets subject to the SH0ES prior imply that γ -1 is O(100) times larger than the Hubble scale, H 0 -1. Considering P18+SH0ES or P18+DES+SH0ES data set combinations, the odds against vanishing γ are over 1000:1 and 2000:1, respectively, and the model is strongly favored over the SM with a deviance information criterion (DIC) gain ≳ 10 and ≳ 12, respectively. The H 0 tension is reduced in this model to ∼ 1.5 and 1.3 σ, respectively. Allowing for a non-vanishing spatial curvature, γ -1 halves to O(50) times H 0 -1. The capacity of two other major cosmological probes, baryonic oscillations and type Ia supernovae, SNIa, to distinguish between the models is also discussed. We conclude that the H 0 tension may simply result from a yet unrecognized fundamental symmetry of the gravitational interaction — Weyl invariance.

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38

Shimon, Meir. "Possible resolution of the Hubble tension with Weyl invariant gravity." Journal of Cosmology and Astroparticle Physics 2022, no. 04 (April 1, 2022): 048. http://dx.doi.org/10.1088/1475-7516/2022/04/048.

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Анотація:

Abstract We explore cosmological implications of a genuinely Weyl invariant (WI) gravitational interaction. The latter reduces to general relativity in a particular conformal frame for which the gravitational coupling and active gravitational masses are fixed. Specifically, we consider a cosmological model in this framework that is dynamically identical to the standard model (SM) of cosmology. However, kinematics of test particles traveling in the new background metric is modified thanks to a new (cosmological) fundamental mass scale, γ, of the model that emerges as an integration constant of the classical field equations. Since the lapse-function of the new metric is radially-dependent any incoming photon experiences (gravitational) red/blueshift in the comoving frame, unlike in the SM. Distance scales are modified as well due to the scale γ. The claimed 4.4σ tension level between the locally measured Hubble constant, H 0, with SH0ES and the corresponding value inferred from the cosmic microwave background (CMB) could then be significantly alleviated by an earlier-than-thought recombination. Assuming vanishing spatial curvature, either one of the Planck 2018 (P18) or dark energy survey (DES) yr1 data sets subject to the SH0ES prior imply that γ -1 is O(100) times larger than the Hubble scale, H 0 -1. Considering P18+SH0ES or P18+DES+SH0ES data set combinations, the odds against vanishing γ are over 1000:1 and 2000:1, respectively, and the model is strongly favored over the SM with a deviance information criterion (DIC) gain ≳ 10 and ≳ 12, respectively. The H 0 tension is reduced in this model to ∼ 1.5 and 1.3 σ, respectively. Allowing for a non-vanishing spatial curvature, γ -1 halves to O(50) times H 0 -1. The capacity of two other major cosmological probes, baryonic oscillations and type Ia supernovae, SNIa, to distinguish between the models is also discussed. We conclude that the H 0 tension may simply result from a yet unrecognized fundamental symmetry of the gravitational interaction — Weyl invariance.

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39

Arendse, Nikki, Radosław J. Wojtak, Adriano Agnello, Geoff C. F. Chen, Christopher D. Fassnacht, Dominique Sluse, Stefan Hilbert, et al. "Cosmic dissonance: are new physics or systematics behind a short sound horizon?" Astronomy & Astrophysics 639 (July 2020): A57. http://dx.doi.org/10.1051/0004-6361/201936720.

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Context. Persistent tension between low-redshift observations and the cosmic microwave background radiation (CMB), in terms of two fundamental distance scales set by the sound horizon rd and the Hubble constant H0, suggests new physics beyond the Standard Model, departures from concordance cosmology, or residual systematics. Aims. The role of different probe combinations must be assessed, as well as of different physical models that can alter the expansion history of the Universe and the inferred cosmological parameters. Methods. We examined recently updated distance calibrations from Cepheids, gravitational lensing time-delay observations, and the tip of the red giant branch. Calibrating the baryon acoustic oscillations and type Ia supernovae with combinations of the distance indicators, we obtained a joint and self-consistent measurement of H0 and rd at low redshift, independent of cosmological models and CMB inference. In an attempt to alleviate the tension between late-time and CMB-based measurements, we considered four extensions of the standard ΛCDM model. Results. The sound horizon from our different measurements is rd = (137 ± 3stat. ± 2syst.) Mpc based on absolute distance calibration from gravitational lensing and the cosmic distance ladder. Depending on the adopted distance indicators, the combined tension in H0 and rd ranges between 2.3 and 5.1 σ, and it is independent of changes to the low-redshift expansion history. We find that modifications of ΛCDM that change the physics after recombination fail to provide a solution to the problem, for the reason that they only resolve the tension in H0, while the tension in rd remains unchanged. Pre-recombination extensions (with early dark energy or the effective number of neutrinos Neff = 3.24 ± 0.16) are allowed by the data, unless the calibration from Cepheids is included. Conclusions. Results from time-delay lenses are consistent with those from distance-ladder calibrations and point to a discrepancy between absolute distance scales measured from the CMB (assuming the standard cosmological model) and late-time observations. New proposals to resolve this tension should be examined with respect to reconciling not only the Hubble constant but also the sound horizon derived from the CMB and other cosmological probes.

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40

Ballardini, Mario, Fabio Finelli, and Domenico Sapone. "Cosmological constraints on the gravitational constant." Journal of Cosmology and Astroparticle Physics 2022, no. 06 (June 1, 2022): 004. http://dx.doi.org/10.1088/1475-7516/2022/06/004.

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Abstract We study the variation of the gravitational constant on cosmological scales in scalar-tensor theories of gravity. We focus on the simplest models of scalar-tensor theories with a coupling to the Ricci scalar of the form F(σ) = N 2 pl + ξσ 2, such as extended Jordan-Brans-Dicke (N pl = 0), or a non-minimally coupled scalar field with N pl = M pl, which permits the gravitational constant to vary self-consistently in time and space. In addition, we allow the effective gravitational constant on cosmological scales to differ from the Newton's measured constant G, i.e. G eff(z = 0) = G(1+Δ)2. We study the impact of this imbalance Δ jointly with the coupling ξ into anisotropies of the cosmic microwave background and matter power spectrum at low-redshift. Combining the information from Planck 2018 CMB temperature, polarization and lensing, together with a compilation of BAO measurements from the release DR12 of the Baryon Oscillation Spectroscopic Survey (BOSS), we constrain the imbalance to Δ = -0.022 ± 0.023 (68% CL) and the coupling parameter to 103 ξ < 0.82 (95% CL) for Jordan-Brans-Dicke and for a non-minimally coupled scalar field with F(σ) = M 2 pl + ξσ 2 we constrain the imbalance to Δ > -0.018 (< 0.021) and the coupling parameter to ξ < 0.089 (ξ > - 0.041) both at 95% CL. With current data, we observe that the degeneracy between Δ, the coupling ξ to the Ricci scalar, and H 0 allows for a larger value of the Hubble constant increasing the consistency between the distance-ladder measurement of the Hubble constant from supernovae type Ia by the SH0ES team and its value inferred by CMB data. We also study how future cosmological observations can constrain the gravitational Newton's constant. Future data such as the combination of CMB anisotropies from LiteBIRD and CMB-S4, and large-scale structures galaxy clustering from DESI and galaxy shear from LSST reduce the uncertainty in Δ to σ(Δ) ≃ 0.004.

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41

Schmidt, Brian P. "Type Ia supernovae as extragalactic distance indicators." Proceedings of the International Astronomical Union 8, S289 (August 2012): 327. http://dx.doi.org/10.1017/s1743921312021631.

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AbstractType Ia supernovae (SNe Ia) are among cosmology's most useful tools for measuring extragalactic distances. Their intrinsic brightness, MV=−19.2 mag, and precision, σ=0.12 mag, make for a unique combination to precisely probe cosmic expansion from the nearby to the high-redshift Universe. I describe the current state of the art for measuring distances to SNe Ia—focusing on the current challenges which ultimately limit their precision—as well as prospects for further refinement. I also highlight cosmological applications where they have been especially valuable, and briefly review some future projects which plan to exploit SNe Ia.

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42

Lü, Lian-Zhong, Yi-Ping Qin, and Fu-Wen Zhang. "Are Type Ia Supernovae Reliable Distance Indicators?" Chinese Journal of Astronomy and Astrophysics 7, no. 5 (October 2007): 649–56. http://dx.doi.org/10.1088/1009-9271/7/5/05.

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43

Sergijenko, O. "Dipole of the luminosity distance as a test for dark energy models." Bulletin of Taras Shevchenko National University of Kyiv. Astronomy, no. 58 (2018): 29–33. http://dx.doi.org/10.17721/btsnua.2018.58.29-33.

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The dependence of Hubble parameter on redshift can be determined directly from the dipole of luminosity distance to Supernovae Ia. We investigate the possibility of using the data on dipole of the luminosity distance obtained from the Supernovae Ia compilations SDSS, Union2.1, JLA and Pantheon to distinguish the dark energy models.

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44

Ajhar, Edward A., John L. Tonry, John P. Blakeslee, Adam G. Riess, and Brian P. Schmidt. "Reconciliation of the Surface Brightness Fluctuation and Type Ia Supernova Distance Scales." Astrophysical Journal 559, no. 2 (October 2001): 584–91. http://dx.doi.org/10.1086/322342.

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45

Blondin, S., K. S. Mandel, and R. P. Kirshner. "Do spectra improve distance measurements of Type Ia supernovae?" Astronomy & Astrophysics 526 (December 24, 2010): A81. http://dx.doi.org/10.1051/0004-6361/201015792.

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46

Fakhouri, H. K., K. Boone, G. Aldering, P. Antilogus, C. Aragon, S. Bailey, C. Baltay, et al. "IMPROVING COSMOLOGICAL DISTANCE MEASUREMENTS USING TWIN TYPE IA SUPERNOVAE." Astrophysical Journal 815, no. 1 (December 9, 2015): 58. http://dx.doi.org/10.1088/0004-637x/815/1/58.

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47

Vinkó, J., K. Sárneczky, K. Takáts, G. H. Marion, T. Hegedüs, I. B. Bíró, T. Borkovits, et al. "Testing supernovae Ia distance measurement methods with SN 2011fe." Astronomy & Astrophysics 546 (September 28, 2012): A12. http://dx.doi.org/10.1051/0004-6361/201220043.

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48

Woosley, S. E., A. S. Almgren, A. J. Aspden, J. B. Bell, D. Kasen, A. R. Kerstein, H. Ma, A. Nonaka, and M. Zingale. "Type Ia supernovae: Advances in large scale simulation." Journal of Physics: Conference Series 180 (July 1, 2009): 012023. http://dx.doi.org/10.1088/1742-6596/180/1/012023.

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49

Riess, Adam G., Louise Breuval, Wenlong Yuan, Stefano Casertano, Lucas M. Macri, J. Bradley Bowers, Dan Scolnic, Tristan Cantat-Gaudin, Richard I. Anderson, and Mauricio Cruz Reyes. "Cluster Cepheids with High Precision Gaia Parallaxes, Low Zero-point Uncertainties, and Hubble Space Telescope Photometry." Astrophysical Journal 938, no. 1 (October 1, 2022): 36. http://dx.doi.org/10.3847/1538-4357/ac8f24.

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Abstract We present Hubble Space Telescope (HST) photometry of 17 Cepheids in open clusters and their cluster mean parallaxes from Gaia EDR3. These parallaxes are more precise than those from individual Cepheids (G < 8 mag) previously used to measure the Hubble constant because they are derived from an average of >300 stars per cluster. Cluster parallaxes also have smaller systematic uncertainty because their stars lie in the range (G > 13 mag) where the Gaia parallax calibration is the most comprehensive. Cepheid photometry employed in the period–luminosity relation was measured using the same HST instrument (WFC3) and filters (F555W, F814W, F160W) as extragalactic Cepheids in Type Ia supernova hosts. We find no evidence of residual parallax offset in this magnitude range, zp = −3 ± 4 μas, consistent with the results from Lindegren et al. and most studies. The Cepheid luminosity (at P = 10 d and solar metallicity) in the HST near-infrared, Wesenheit magnitude system derived from the cluster sample is M H , 1 W = − 5.902 ± 0.025 mag and −5.890 ± 0.018 mag with or without simultaneous determination of a parallax offset, respectively. These results are similar to measurements from field Cepheids, confirming the accuracy of the Gaia parallaxes over a broad range of magnitudes. The SH0ES distance ladder calibrated only from this sample gives H 0 = 72.9 ± 1.3 and H 0 = 73.3 ± 1.1 km s−1 Mpc−1 with or without offset marginalization; combined with all other anchors we find H 0 = 73.01 ± 0.99 and 73.15 ± 0.97 km s−1 Mpc−1, respectively, a 5% or 7% reduction in the uncertainty in H 0 and a ∼5.3σ Hubble tension relative to Planck+ΛCDM. It appears increasingly difficult to reconcile two of the best-measured cosmic scales, parallaxes from Gaia and the angular size of the acoustic scale of the cosmic microwave background, using the simplest form of ΛCDM to connect the two.

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Bergh, Sidney van den. "Astronomy: Supernovae and the distance scale." Nature 314, no. 6009 (March 1985): 320. http://dx.doi.org/10.1038/314320a0.

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Статті в журналах з теми "Supernovae Ia distance scale"

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