Articles de revues sur le sujet « NGC 2992 »

Pour voir les autres types de publications sur ce sujet consultez le lien suivant : NGC 2992.

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres

Choisissez une source :

Consultez les 50 meilleurs articles de revues pour votre recherche sur le sujet « NGC 2992 ».

À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.

Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.

Parcourez les articles de revues sur diverses disciplines et organisez correctement votre bibliographie.

1

Joshi, U. C., Rekha Jain et M. R. Deshpande. « Photopolarimetry of Seyfert Galaxies - NGC 2992, NGC 3081, NGC 3227 and IC 4329 A ». Symposium - International Astronomical Union 134 (1989) : 321–22. http://dx.doi.org/10.1017/s0074180900141208.

Texte intégral
Résumé :
Photopolarimetric observations in UBVRI bands of Seyfert galaxies NGC 2992, NGC 3081, NGC 3227 and IC 4329A were carried between 1984–87. Measurements were made with PRL polarimeter (Deshpande et al. 1985) on 1 meter telescope of Indian Institute of Astrophysics, Kavalur. Method of observations and reduction is same as discussed elsewhere (Joshi et al. 1987).
Styles APA, Harvard, Vancouver, ISO, etc.
2

Allen, Mark G., Michael A. Dopita, Zlatan I. Tsvetanov et Ralph S. Sutherland. « Physical Conditions in the Seyfert Galaxy NGC 2992 ». Astrophysical Journal 511, no 2 (février 1999) : 686–708. http://dx.doi.org/10.1086/306718.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Beckmann, V., N. Gehrels et J. Tueller. « The 1–200 keV X‐Ray Spectrum of NGC 2992 and NGC 3081 ». Astrophysical Journal 666, no 1 (septembre 2007) : 122–27. http://dx.doi.org/10.1086/519486.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Veilleux, S., P. L. Shopbell et S. T. Miller. « The Biconical Outflow in the Seyfert Galaxy NGC 2992 ». Astronomical Journal 121, no 1 (janvier 2001) : 198–209. http://dx.doi.org/10.1086/318046.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Yaqoob, Tahir, Kendrah D. Murphy et Yuichi Terashima. « An accretion disk laboratory in the Seyfert 1.9 galaxy NGC 2992 ». Proceedings of the International Astronomical Union 2, S238 (août 2006) : 123–26. http://dx.doi.org/10.1017/s1743921307004826.

Texte intégral
Résumé :
AbstractOver twenty five years of X-ray observations of the Seyfert 1.9 galaxy NGC 2992 show that it is a promising test-bed for severely constraining accretion disk models. The previous interpretation of the historical activity of NGC 2992 in terms of the accretion disk slowly becoming dormant over many years and then ‘re-building’ itself is not supported by new data. A recent year-long monitoring campaign with RXTE showed that the X-ray continuum varied by more than an order of magnitude on a timescale of weeks. During the large-amplitude flares the centroid energy of the Fe K emission-line complex became significantly redshifted, indicating that the violent activity was occurring close to the putative central black hole where gravitational energy shifts can be sufficiently large. For the continuum, the Compton-y parameter remains roughly constant despite the large-amplitude luminosity variability, with (kT) τ ∼ 20–50.
Styles APA, Harvard, Vancouver, ISO, etc.
6

Colina, L., K. J. Fricke, W. Kollatschny et M. A. C. Perryman. « Extended Line Emitting Regions in the Seyfert Galaxy NGC 2992 ». Symposium - International Astronomical Union 121 (1987) : 131–33. http://dx.doi.org/10.1017/s0074180900155020.

Texte intégral
Résumé :
NGC 2992 is a nearby Seyfert galaxy (z=0.008, 1″=150 pc, for HO=75 km s−1 Mpc−1) seen almost edge-on (i=70°). A dust lane crossing the galaxy has been detected (Burbidge et al. 1972, see also Fig. 1) and the presence of two extended radio-emitting regions at position angles P.A. 130° and P.A. 160° has been reported (Ulvestad and Wilson, 1984).
Styles APA, Harvard, Vancouver, ISO, etc.
7

Friedrich, S., R. I. Davies, E. K. S. Hicks, H. Engel, F. Müller-Sánchez, R. Genzel et L. J. Tacconi. « Adaptive optics near infrared integral field spectroscopy of NGC 2992 ». Astronomy and Astrophysics 519 (septembre 2010) : A79. http://dx.doi.org/10.1051/0004-6361/200913924.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

Lösch, Elismar, et Daniel Ruschel-Dutra. « Testing the link between mergers and AGN in the Arp 245 system ». Proceedings of the International Astronomical Union 15, S359 (mars 2020) : 192–94. http://dx.doi.org/10.1017/s1743921320001842.

Texte intégral
Résumé :
AbstractGalaxy mergers are known to drive an inflow of gas towards galactic centers, potentia- lly leading to both star formation and nuclear activity. In this work we aim to study how a major merger event in the ARP 245 system is linked with the triggering of an active galactic nucleus (AGN) in the NGC galaxy 2992. We employed three galaxy collision numerical simulations and calculated the inflow of gas through four different concentric spherical surfaces around the galactic centers, estimating an upper limit for the luminosity of an AGN being fed the amount of gas crossing the innermost spherical surface. We found that these simulations predict reasonable gas inflow rates when compared with the observed AGN luminosity in NGC 2992.
Styles APA, Harvard, Vancouver, ISO, etc.
9

Kollatschny, W. « Merging Galaxies with Active Nuclei ». Symposium - International Astronomical Union 186 (1999) : 358. http://dx.doi.org/10.1017/s0074180900113051.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Colbert, Edward J. M., David K. Strickland, Sylvain Veilleux et Kimberly A. Weaver. « Extranuclear X‐Ray Emission in the Edge‐on Seyfert Galaxy NGC 2992 ». Astrophysical Journal 628, no 1 (20 juillet 2005) : 113–28. http://dx.doi.org/10.1086/430734.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
11

Xu, Xiaoyu, et Junfeng Wang. « Revisiting the Circumnuclear X-Ray Emission of NGC 2992 in a Historically Low State ». Astrophysical Journal 938, no 2 (1 octobre 2022) : 127. http://dx.doi.org/10.3847/1538-4357/ac912f.

Texte intégral
Résumé :
Abstract The innermost region of the Seyfert galaxy NGC 2992 has long been suspected to be the location of intense AGN–host galaxy interaction, but photon pile up in previous high-resolution observations hampered the study of the soft X-ray excess and the interaction near its nucleus. We present an X-ray imaging and spectroscopic analysis of the circumnuclear (1″–3″) region of NGC 2992 using the zeroth-order image of a 135 ks grating observation obtained with Chandra, which captured the nucleus in a historically low flux state. Extended soft X-ray emission is detected in the circumnuclear region with an observed luminosity of L X ∼ 7 × 1039 erg s−1. The majority of the previous, puzzling detection of soft excess could be associated with the outflow, indicated by the morphological correspondences between the soft X-ray emission and figure-eight-shaped radio bubbles. An anomalous narrow emission line with a centroid energy of ∼4.97 keV is found. If attributed to redshifted highly ionized iron emission (e.g., Fe xxv), the required outflow velocity is ∼0.23 c. An alternative explanation is that this line emission could be produced by the nuclear spallation of iron. We also find extended, asymmetric Fe Kα emission along the galactic disk, which could originate from reflection by cold gas on ∼200 pc scale.
Styles APA, Harvard, Vancouver, ISO, etc.
12

Trippe, M. L., D. M. Crenshaw, R. Deo et M. Dietrich. « LONG-TERM VARIABILITY IN THE OPTICAL SPECTRUM OF THE SEYFERT GALAXY NGC 2992 ». Astronomical Journal 135, no 6 (1 mai 2008) : 2048–54. http://dx.doi.org/10.1088/0004-6256/135/6/2048.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
13

García-Lorenzo, B., S. Arribas et E. Mediavilla. « Stellar and ionized gas kinematics of the interacting Seyfert 1.9 galaxy NGC 2992 ». Astronomy & ; Astrophysics 378, no 3 (novembre 2001) : 787–99. http://dx.doi.org/10.1051/0004-6361:20011243.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
14

Busko, I. C., et J. E. Steiner. « “On the Broad Hα Component of IC 5063, IC 5135 and NGC 2992” ». Symposium - International Astronomical Union 134 (1989) : 90–92. http://dx.doi.org/10.1017/s0074180900140446.

Texte intégral
Résumé :
As part of a high resolution (0.55Å) spectroscopic survey of southern Seyfert galaxies, we observed a number of objects in the Hα region. The main goal of this survey is to study the profiles of the narrow lines in Seyfert 1 and Seyfert 2 galaxies. As a by-product, one can search for and analyse weak broad components in Ha that sometimes show up when Seyfert 2 galaxies are observed with high resolution and high signal to noise. Such objects are usually classified as Seyfert 1.8 or 1.9. The search and detailed study of these objects is of great importance for characterizing the weak end of the luminosity function of active galactic nuclei (AGN). The observations were made with a two channel intensified Reticon at the Coude spectrograph of the 1.6m telescope at the Laboratorio Nacional de Astrofisica (CNPq/LNA).
Styles APA, Harvard, Vancouver, ISO, etc.
15

Murphy, K. D., M. A. Nowak et H. L. Marshall. « The Nuclear X-Ray Emission-line Structure in NGC 2992 Revealed byChandra-HETGS ». Astrophysical Journal 840, no 2 (15 mai 2017) : 120. http://dx.doi.org/10.3847/1538-4357/aa6d6a.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
16

Fernandez, Luis C., Nathan J. Secrest, Megan C. Johnson, Henrique R. Schmitt, Travis C. Fischer, Phillip J. Cigan et Bryan N. Dorland. « FRAMEx. II. Simultaneous X-Ray and Radio Variability in Active Galactic Nuclei—The Case of NGC 2992 ». Astrophysical Journal 927, no 1 (1 mars 2022) : 18. http://dx.doi.org/10.3847/1538-4357/ac4b5f.

Texte intégral
Résumé :
Abstract Using simultaneous Very Long Baseline Array and Neil Gehrels Swift Observatory X-ray Telescope observations of the active galactic nucleus (AGN) in NGC 2992 over a six-month observing campaign, we observed a large drop in core 5 cm radio luminosity, by a factor of >3, in tandem with a factor of >5 increase in 2–10 keV X-ray luminosity. While NGC 2992 has long been an important object for studies of X-ray variability, our study is the first simultaneous X-ray and radio variability campaign for this object. We observe that the X-ray spectral index does not change over the course of the flare, consistent with a change in the bulk amount of Comptonizing plasma, potentially due to a magnetic reconnection event in the accretion disk. The drop in apparent radio luminosity can be explained by a change in free–free absorption, which we calculate to correspond to an ionized region with a physical extent and electron density consistent with the broad-line region (BLR). Our results are consistent with magnetic reconnection events in the dynamic accretion disk creating outbursts of ionizing material, increasing Compton up-scattering of UV accretion disk photons and feeding material into the BLR. These findings present an important physical picture for the dynamical relationship between X-ray and radio emission in AGNs.
Styles APA, Harvard, Vancouver, ISO, etc.
17

Weaver, K. A., J. Nousek, T. Yaqoob, R. F. Mushotzky, F. Makino et C. Otani. « X-Ray Reprocessing by a Molecular Torus in the Seyfert 1.9 Galaxy NGC 2992 ». Astrophysical Journal 458 (février 1996) : 160. http://dx.doi.org/10.1086/176800.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
18

Duc, P. A., E. Brinks, V. Springel, B. Pichardo, P. Weilbacher et I. F. Mirabel. « Formation of a Tidal Dwarf Galaxy in the Interacting System Arp 245 (NGC 2992/93) ». Astronomical Journal 120, no 3 (septembre 2000) : 1238–64. http://dx.doi.org/10.1086/301516.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
19

Guolo-Pereira, Muryel, et Daniel Ruschel-Dutra. « Mapping the inner kpc of the interacting Seyfert galaxy NGC 2992 : Stellar populations and gas kinematics ». Proceedings of the International Astronomical Union 15, S359 (mars 2020) : 288–90. http://dx.doi.org/10.1017/s1743921320002288.

Texte intégral
Résumé :
AbstractWe present Gemini Multi-Object Spectrograph Integral Field Unit (GMOS-IFU) observations of the inner 1.1 kpc of the interacting Seyfert galaxy NGC 2992. From full spectral synthesis we found that the stellar population is mainly (up to 80 per cent of the total light) composed by an old (t ≥ 1.4 Gyr) metal-rich (Z ≥ 2.0) populations with a smaller but considerable contribution (up to 30 per cent) from young (t ≤ 100 Myr) metal-poor (Z ≥ 1.0) populations. The gas kinematics presents two main components: one from gas in orbit in the galaxy disk and an outflow with mass outflow rate of ˜2 Mʘ yr–1 and a kinematic power of ˜ 2 × 1040 erg s–1.
Styles APA, Harvard, Vancouver, ISO, etc.
20

Marinucci, A., S. Bianchi, V. Braito, B. De Marco, G. Matt, R. Middei, E. Nardini et J. N. Reeves. « The lively accretion disc in NGC 2992 – I. Transient iron K emission lines in the high-flux state ». Monthly Notices of the Royal Astronomical Society 496, no 3 (13 juin 2020) : 3412–23. http://dx.doi.org/10.1093/mnras/staa1683.

Texte intégral
Résumé :
ABSTRACT We report on one of the brightest flux levels of the Seyfert 2 galaxy NGC 2992 ever observed in X-rays, on 2019 May. The source has been monitored every few days from 2019 March 26 to 2019 December 14 by Swift-X-Ray Telescope (XRT), and simultaneous XMM–Newton (250 ks) and NuSTAR (120 ks) observations were triggered on 2019 May 6. The high count rate of the source (its 2–10 keV flux ranged between 0.7 and 1.0 × 10−10 erg cm−2 s−1) allows us to perform a time-resolved spectroscopy, probing spatial scales of tens of gravitational radii from the central black hole. By constructing a map of the excess emission over the primary continuum, we find several emission structures in the 5.0–7.2 keV energy band. From fitting the 50 European Photon Imaging Camera (EPIC)-pn spectral slices of ∼5 ks duration, we interpret them as a constant narrow iron Kα line and three variable components in the iron K complex. When a self-consistent model accounting for the accretion disc emission is considered (KYNrline), two of these features (in the 5.0–5.8 and 6.8–7.2 keV bands) can be ascribed to a flaring region of the accretion disc located at rin ≃ 15–40rg from the black hole. The third one (6.5–6.8 keV) is likely produced at much larger radii (rin > 50rg). The inner radius and the azimuthal extension retrieved from the co-added spectra of the flaring states are rin = 15 ± 3rg and ϕ = 165°–330°, suggesting that the emitting region responsible for the broad iron K component is a relatively compact annular sector within the disc. Our findings support a physical scenario in which the accretion disc in NGC 2992 becomes more active at high accretion rates ($L_{\rm bol}/L_{\rm Edd}\ge 4$ per cent).
Styles APA, Harvard, Vancouver, ISO, etc.
21

Guolo-Pereira, Muryel, Daniel Ruschel-Dutra, Thaisa Storchi-Bergmann, Allan Schnorr-Müller, Roberto Cid Fernandes, Guilherme Couto, Natacha Dametto et Jose A. Hernandez-Jimenez. « Exploring the AGN-merger connection in Arp 245 I : Nuclear star formation and gas outflow in NGC 2992 ». Monthly Notices of the Royal Astronomical Society 502, no 3 (29 janvier 2021) : 3618–37. http://dx.doi.org/10.1093/mnras/stab245.

Texte intégral
Résumé :
ABSTRACT Galaxy mergers are central to our understanding of galaxy formation, especially within the context of hierarchical models. Besides having a large impact on the star formation history, mergers are also able to influence gas motions at the centre of galaxies and trigger an active galactic nucleus (AGN). In this paper, we present a case study of the Seyfert galaxy NGC 2992, which together with NGC 2993 forms the early-stage merger system Arp 245. Using Gemini Multi-Object Spectrograph integral field unit data from the inner 1.1 kpc of the galaxy, we were able to spatially resolve the stellar populations, the ionization mechanism, and kinematics of ionized gas. From full spectral synthesis, we found that the stellar population is primarily composed by old metal-rich stars (t ≥ 1.4 Gyr, Z ≥ 2.0 Z⊙), with a contribution of at most 30 per cent of the light from a young and metal-poor population (t ≤ 100 Myr, Z ≤ 1.0 Z⊙). We detect H α and H β emission from the broad-line region with a full width at half-maximum of ∼2000 $\rm km\, s^{-1}$. The narrow-line region kinematics presents two main components: one from gas orbiting the galaxy disc and a blueshifted (velocity ≈ −200 $\rm km\, s^{-1}$) outflow, possibly correlated with the radio emission, with mass outflow rate of ∼2 M⊙ yr−1 and a kinematic power of ∼2 × 1040 erg s−1 ($\dot{E}_{\mathrm{ out}}$/Lbol ≈ 0.2 per cent). We also show even though the main ionization mechanism is the AGN radiation, ionization by young stars and shocks may also contribute to the emission line ratios presented in the innermost region of the galaxy.
Styles APA, Harvard, Vancouver, ISO, etc.
22

Yaqoob, Tahir, Kendrah D. Murphy, Richard E. Griffiths, Yoshito Haba, Hajime Inoue, Takeshi Itoh, Richard Kelley et al. « Precision Fe Kα and Fe Kβ Line Spectroscopy of the Seyfert 1.9 Galaxy NGC 2992 with Suzaku ». Publications of the Astronomical Society of Japan 59, sp1 (30 janvier 2007) : S283—S299. http://dx.doi.org/10.1093/pasj/59.sp1.s283.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
23

Ptak, Andrew, Tahir Yaqoob et Kendra Murphy. « Precision Fe Kalpha and Fe Kbeta Line Spectroscopy of the Seyfert 1.9 Galaxy NGC 2992 with Suzaku ». Progress of Theoretical Physics Supplement 169 (2007) : 252–55. http://dx.doi.org/10.1143/ptps.169.252.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
24

Murphy, Kendrah D., Tahir Yaqoob et Yuichi Terashima. « Monitoring the Violent Activity from the Inner Accretion Disk of the Seyfert 1.9 Galaxy NGC 2992 withRXTE ». Astrophysical Journal 666, no 1 (septembre 2007) : 96–108. http://dx.doi.org/10.1086/520039.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
25

Wehrle, Ann E., et Mark Morris. « Radio and H-alpha images of the 'figure-8' radio nucleus of the interacting Seyfert galaxy NGC 2992 ». Astronomical Journal 95 (juin 1988) : 1689. http://dx.doi.org/10.1086/114765.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
26

Chapman, S. C., S. L. Morris, A. Alonso-Herrero et H. Falcke. « Adaptive optics near-infrared imaging of NGC 2992 -- unveiling core structures related to radio figure-of-8 loops ». Monthly Notices of the Royal Astronomical Society 314, no 2 (11 mai 2000) : 263–72. http://dx.doi.org/10.1046/j.1365-8711.2000.03303.x.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
27

Marinucci, A., S. Bianchi, V. Braito, G. Matt, E. Nardini et J. Reeves. « Tracking the iron K α line and the ultra fast outflow in NGC 2992 at different accretion states ». Monthly Notices of the Royal Astronomical Society 478, no 4 (2 juin 2018) : 5638–49. http://dx.doi.org/10.1093/mnras/sty1436.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
28

García-Bernete, I., C. Ramos Almeida, J. A. Acosta-Pulido, A. Alonso-Herrero, M. Sánchez-Portal, M. Castillo, M. Pereira-Santaella et al. « The nuclear and extended infrared emission of the Seyfert galaxy NGC 2992 and the interacting system Arp 245 ». Monthly Notices of the Royal Astronomical Society 449, no 2 (23 mars 2015) : 1309–26. http://dx.doi.org/10.1093/mnras/stv338.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
29

Brinks, Elias, Pierre-Alain Duc et Fabian Walter. « VLA HI and OVRO CO Interferometry of a Tidal Dwarf Galaxy ». Symposium - International Astronomical Union 217 (2004) : 532–37. http://dx.doi.org/10.1017/s0074180900198328.

Texte intégral
Résumé :
We present high resolution interferometric observations of the cool atomic and cold molecular ISM of the TDG candidate Arp 245N, an object resembling a dwarf galaxy in the northern tidal tail of the interacting system NGC 2992/3. We observed the HI line with the NRAO VLA and the CO(1→0) transition with the OVRO millimeter interferometer at 5“ – 6” angular resolution (750 pc linear resolution). These datacubes offer the required spatial and velocity resolution to determine whether the mass concentration near the tip of the tail is a genuine feature, and hence a good TDG candidate, or an artefact caused by a fortuitous alignment of our line of sight with the direction of the tail. A preliminary analysis seems to confirm that Arp 245N is a self-gravitating entity.
Styles APA, Harvard, Vancouver, ISO, etc.
30

Ghosh, Ritesh, et Main Pal. « The Correlated Response of the Narrow FeKα Emission Line to the Primary Continuum Changes in the Seyfert Galaxy NGC 2992 ». Research Notes of the AAS 5, no 2 (1 février 2021) : 35. http://dx.doi.org/10.3847/2515-5172/abe863.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
31

Shu, X. W., T. Yaqoob, K. D. Murphy, V. Braito, J. X. Wang et W. Zheng. « NGC 2992 IN AN X-RAY HIGH STATE OBSERVED BYXMM-NEWTON : RESPONSE OF THE RELATIVISTIC Fe Kα LINE TO THE CONTINUUM ». Astrophysical Journal 713, no 2 (1 avril 2010) : 1256–65. http://dx.doi.org/10.1088/0004-637x/713/2/1256.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
32

Busko, I. C., et J. E. Steiner. « Profiles of emission lines in active galactic nuclei - III. Observations of Ha, [N II] and [S II] profiles ». Monthly Notices of the Royal Astronomical Society 245, no 3 (1 août 1990) : 470. http://dx.doi.org/10.1093/mnras/245.3.470.

Texte intégral
Résumé :
Summary High-resolution (FWHM= 28 km s-1) observations of Ha, [N II] λ6548/6583 and [S II] λ6717/6731 emission lines in several southern active galactic nuclei (AGN) are presented. Deblending of the Hα + [N II] profiles was performed using, when available, the [0 III] λ5007 profile shape as a template. Line profile measurements, as well as line intensities, are tabulated. We found to be relatively common among the observed objects the existence of structure in the line cores, pointing to the complexity of the dynamics in the low-velocity emission region. Differences in profile shape and width amongst different lines are also common, indicating that often there is a superposition, on the spectrograph slit, of emission regions with different dynamics and excitation conditions. This superposition is quantified in the case of IC 5063. We found weak, broad Ha emission in IC 5063 and IC 5135. In NGC 2992, we were unable to confirm the presence of a broad Ha component with the same intensity as found by previous authors, which we ascribe to spectral resolution effects.
Styles APA, Harvard, Vancouver, ISO, etc.
33

Hess, Kelley M., D. J. Pisano, Eric M. Wilcots et Jayaram N. Chengalur. « ANOMALOUS H I IN NGC 2997 ». Astrophysical Journal 699, no 1 (10 juin 2009) : 76–88. http://dx.doi.org/10.1088/0004-637x/699/1/76.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
34

Walsh, J. R., et Jean-Rene Roy. « The abundance gradient across the galaxy NGC 2997 ». Astrophysical Journal 341 (juin 1989) : 722. http://dx.doi.org/10.1086/167531.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
35

Grosbøl, P., H. Dottori et R. Gredel. « Star-forming knots and density wave in NGC 2997 ». Astronomy & ; Astrophysics 453, no 2 (16 juin 2006) : L25—L28. http://dx.doi.org/10.1051/0004-6361:20065446.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
36

Grosbøl, P., et H. Dottori. « Pattern speed of main spiral arms in NGC 2997 ». Astronomy & ; Astrophysics 499, no 3 (5 mai 2009) : L21—L24. http://dx.doi.org/10.1051/0004-6361/200911805.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
37

Ho, I.-Ting, Sharon E. Meidt, Rolf-Peter Kudritzki, Brent A. Groves, Mark Seibert, Barry F. Madore, Eva Schinnerer, Jeffrey A. Rich, Chiaki Kobayashi et Lisa J. Kewley. « Azimuthal variations of gas-phase oxygen abundance in NGC 2997 ». Astronomy & ; Astrophysics 618 (octobre 2018) : A64. http://dx.doi.org/10.1051/0004-6361/201833262.

Texte intégral
Résumé :
The azimuthal variation of the H II region oxygen abundance in spiral galaxies is a key observable for understanding how quickly oxygen produced by massive stars can be dispersed within the surrounding interstellar medium. Observational constraints on the prevalence and magnitude of such azimuthal variations remain rare in the literature. Here, we report the discovery of pronounced azimuthal variations of H II region oxygen abundance in NGC 2997, a spiral galaxy at approximately 11.3 Mpc. Using 3D spectroscopic data from the TYPHOON Program, we have studied the H II region oxygen abundance at a physical resolution of 125 pc. Individual H II regions or complexes are identified in the 3D optical data and their strong emission line fluxes measured to constrain their oxygen abundances. We find 0.06 dex azimuthal variations in the oxygen abundance on top of a radial abundance gradient that is comparable to those seen in other star-forming disks. At a given radial distance, the oxygen abundances are highest in the spiral arms and lower in the inter-arm regions, similar to what has been reported in NGC 1365 using similar observations. We discuss whether the azimuthal variations could be recovered when the galaxy is observed at worse physical resolutions and lower signal-to-noise ratios.
Styles APA, Harvard, Vancouver, ISO, etc.
38

Pisano, D. J. « GREEN BANK TELESCOPE OBSERVATIONS OF LOW COLUMN DENSITY H I AROUND NGC 2997 AND NGC 6946 ». Astronomical Journal 147, no 3 (21 janvier 2014) : 48. http://dx.doi.org/10.1088/0004-6256/147/3/48.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
39

Elmegreen, Debra Meloy, Frederick R. Chromey, Jessica E. Sawyer et Erika L. Reinfeld. « Near-Infrared Observations of Hot Spots in the Circumnuclear Rings of NGC 2997 and NGC 6951 ». Astronomical Journal 118, no 2 (août 1999) : 777–84. http://dx.doi.org/10.1086/300970.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
40

Ho, I.-Ting. « Go beyond radial gradient : azimuthal variations of ISM abundance in 3D ». Proceedings of the International Astronomical Union 14, A30 (août 2018) : 259. http://dx.doi.org/10.1017/s1743921319004253.

Texte intégral
Résumé :
AbstractUsing 3D spectroscopy data from the TYPHOON Project (PI: B. Madore), I show convincing observational evidence that the ISM oxygen abundance traced by HII regions presents systematic azimuthal variations in NGC 1365 and NGC 2997. I discuss a possible physical origin and on-going efforts to explore the prevalence and cause of such variations.
Styles APA, Harvard, Vancouver, ISO, etc.
41

Grosbøl, P., H. Dottori et R. Gredel. « Young stellar clusters triggered by a density wave in NGC 2997 ». Proceedings of the International Astronomical Union 2, S237 (août 2006) : 417. http://dx.doi.org/10.1017/s1743921307002050.

Texte intégral
Résumé :
AbstractBright knots along the arms of grand-design spiral galaxies are frequently seen on near-infrared K-band images. To investigate their nature, low resolution K-band spectra of a string of knots in the southern arm of the grand design, spiral galaxy NGC 2997 were obtained with ISAAC/VLT. Most of the knots show strong Brγ emission while some have H2 and HeI emission. A few knots show indications of CO absorption. Their spectra and absolute K magnitudes exceeding -12 mag suggest them to be very compact, young stellar clusters with masses up to 5 × 104 M. The knots' azimuthal distance from the K-band spiral correlates well with their Brγ strength, indicating that they are located inside the co-rotation of the density wave, which triggered them through a large-scale, star-forming front. These relative azimuthal distances suggest an age spread of more than 1.6 Myr, which is incompatible with standard models for an instantaneous star burst. This indicates a more complex star-formation history, such as several bursts or continuous formation.
Styles APA, Harvard, Vancouver, ISO, etc.
42

Fitt, A. J., N. A. Howarth, P. Alexander et A. N. Lasenby. « The spatial correlation between far-infrared and radio emission in galaxies – I. NGC 6946, M51, NGC 2997 and M83 ». Monthly Notices of the Royal Astronomical Society 255, no 1 (mars 1992) : 146–64. http://dx.doi.org/10.1093/mnras/255.1.146.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
43

Ryon, J. E., A. Adamo, N. Bastian, L. J. Smith, J. S. Gallagher, I. S. Konstantopoulos, S. Larsen, E. Silva-Villa et E. Zackrisson. « THE SNAPSHOTHUBBLEU-BAND CLUSTER SURVEY (SHUCS). II. THE STAR CLUSTER POPULATION OF NGC 2997 ». Astronomical Journal 148, no 2 (9 juillet 2014) : 33. http://dx.doi.org/10.1088/0004-6256/148/2/33.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
44

Roy, Jean-Rene, Julien Belley et J. R. Walsh. « The structure of giant extragalactic H II regions in NGC 1365, 1566, and 2997 ». Astronomical Journal 97 (avril 1989) : 1010. http://dx.doi.org/10.1086/115045.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
45

Sadakane, Kozo, Takeo Yokoo, Jun-ichi Arimoto, Katsura Matsumoto, Satoshi Honda, Kazuhito Tanabe, Ken-ichi Wakamatsu, Mitsugu Nishida, Michitoshi Yoshida et Masahide Takada-Hidai. « Type-Ia Supernova SN 1995D in NGC 2962 : OpticalV,R, andIBand Photometry and Spectra ». Publications of the Astronomical Society of Japan 48, no 1 (1 février 1996) : 51–57. http://dx.doi.org/10.1093/pasj/48.1.51.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
46

Walsh, J. R., K. Nandy, G. I. Thompson et J. Meaburn. « The properties of the nuclei of the two hot spot galaxies NGC 1097 and 2997 ». Monthly Notices of the Royal Astronomical Society 220, no 2 (1 mai 1986) : 453–71. http://dx.doi.org/10.1093/mnras/220.2.453.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
47

Roy, J. R., et J. R. Walsh. « Imaging spectrophotometry of a chain of giant H II regions in the galaxy NGC 2997 ». Monthly Notices of the Royal Astronomical Society 228, no 4 (1 octobre 1987) : 883–905. http://dx.doi.org/10.1093/mnras/228.4.883.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
48

Denewer, Adel, Khalid Atallah, Khaled Abdel Wahab, Emad Hamed, Basel Refky, Amr Abouzid, Ziad Emarah et al. « Surgery after neoadjuvant chemotherapy for muscle invasive bladder cancer : clinicopathological and surgical outcomes ». International Surgery Journal 5, no 9 (25 août 2018) : 2967. http://dx.doi.org/10.18203/2349-2902.isj20183716.

Texte intégral
Résumé :
Background: Neoadjuvant chemotherapy (NAC) before radical cystectomy (RC) is the standard of care for muscle-invasive bladder cancer (MIBC) owing to the survival advantage, which has correlated with down-staging of the cancer to pT0. This approach is underused because it may be associated with increased perioperative morbidity and mortality rates. This study was designed to evaluate NAC plus RC regarding pathological response, perioperative morbidity and mortality outcomes. Methods: This is a prospective study that was carried out from August 2015 till July 2017 for patients with bladder carcinoma. We enrolled all cases with ≥ T2 bladder receiving NAC. Patients with metastatic disease, poor performance were excluded from this study.Results: pathological response rate and Complications occurred within 30 and 90 d after surgery. Heterologous blood transfusions, length of stay, readmission, and perioperative morbidity, and mortality were compared.Conclusions: Our results suggest that non-urothelial tumor showed no response to Platinum based combination chemotherapeutic regimens. NAC followed by RC gives no more perioperative complications.
Styles APA, Harvard, Vancouver, ISO, etc.
49

Bartek, Jiri, et Zdenek Hodny. « PARK2 orchestrates cyclins to avoid cancer ». Nature Genetics 46, no 6 (28 mai 2014) : 527–28. http://dx.doi.org/10.1038/ng.2992.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
50

Wong, Pearl, Rafael Gaszynki et Yasser Farooque. « N-acetylcysteine therapy for ischaemic hepatic failure : a successful antidote ». International Surgery Journal 8, no 5 (28 avril 2021) : 1586. http://dx.doi.org/10.18203/2349-2902.isj20211834.

Texte intégral
Résumé :
Acute liver failure (ALF) is characterised by severe liver injury with the onset of coagulopathy (INR ≥1.5) and encephalopathy in the absence of pre-existing liver disease. It is associated with a high mortality rate of 10-57%, which is largely driven by multi-organ failure, sepsis and cardiac arrhythmia. Current management focuses on identifying and treating the aetiology, providing supportive care and monitoring liver function. The use of N-acetylcysteine (NAC) therapy is well-studied in the treatment of paracetamol toxicity but is controversial in other causes of ALF. We reported the first case of ischaemic hepatic failure secondary to prolonged portal vein occlusion treated with 72 hours of NAC therapy. Although ischaemic hepatopathy is a relatively uncommon cause of ALF, it is associated with a high mortality rate. The case highlights how early use of NAC therapy may improve hepatic serology biomarkers and should warrant consideration in ALF secondary to ischaemic hepatopathy.
Styles APA, Harvard, Vancouver, ISO, etc.
Nous offrons des réductions sur tous les plans premium pour les auteurs dont les œuvres sont incluses dans des sélections littéraires thématiques. Contactez-nous pour obtenir un code promo unique!

Vers la bibliographie