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Academic literature on the topic 'ROABP'

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Published: 6 September 2023

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Journal articles on the topic "ROABP"

1

Agrawal, Manindra, Rohit Gurjar, Arpita Korwar, and Nitin Saxena. "Hitting-Sets for ROABP and Sum of Set-Multilinear Circuits." SIAM Journal on Computing 44, no. 3 (January 2015): 669–97. http://dx.doi.org/10.1137/140975103.

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Balona, L. A. "Rapidly oscillating TESS A–F main-sequence stars: are the roAp stars a distinct class?" Monthly Notices of the Royal Astronomical Society 510, no. 4 (January 8, 2022): 5743–59. http://dx.doi.org/10.1093/mnras/stac011.

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ABSTRACT From sector 1–44 TESS observations, 19 new rapidly oscillating Ap (roAp) stars, 103 ostensibly non-peculiar stars with roAp-like frequencies, and 617 δ Scuti stars with independent frequencies typical of roAp stars were found. Examination of all chemically peculiar stars observed by TESS resulted in the discovery of 199 Ap stars that pulsate as δ Sct or γ Dor variables. The fraction of pulsating Ap stars is the same as the fraction of pulsating chemically normal stars. There is no distinct separation in frequency or radial order between chemically peculiar δ Sct stars and roAp stars. In fact, all the features that originally distinguished roAp from δ Sct stars in the past have disappeared. There is no reason to assume that the high frequencies in roAp stars are driven by a different mechanism from the high frequencies in chemically normal stars. However, chemically peculiar stars are far more likely to pulsate with high frequencies. The term ‘roAp’ should be dropped: all roAp stars are normal δ Scuti stars.
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Holdsworth, D. L., M. S. Cunha, D. W. Kurtz, V. Antoci, D. R. Hey, D. M. Bowman, O. Kobzar, et al. "TESS cycle 1 observations of roAp stars with 2-min cadence data." Monthly Notices of the Royal Astronomical Society 506, no. 1 (May 31, 2021): 1073–110. http://dx.doi.org/10.1093/mnras/stab1578.

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ABSTRACT We present the results of a systematic search for new rapidly oscillating Ap (roAp) stars using the 2-min cadence data collected by the Transiting Exoplanet Survey Satellite (TESS) during its Cycle 1 observations. We identify 12 new roAp stars. Amongst these stars we discover the roAp star with the longest pulsation period, another with the shortest rotation period, and six with multiperiodic variability. In addition to these new roAp stars, we present an analysis of 44 known roAp stars observed by TESS during Cycle 1, providing the first high-precision and homogeneous sample of a significant fraction of the known roAp stars. The TESS observations have shown that almost 60 per cent (33) of our sample of stars are multiperiodic, providing excellent cases to test models of roAp pulsations, and from which the most rewarding asteroseismic results can be gleaned. We report four cases of the occurrence of rotationally split frequency multiplets that imply different mode geometries for the same degree modes in the same star. This provides a conundrum in applying the oblique pulsator model to the roAp stars. Finally, we report the discovery of non-linear mode interactions in α Cir (TIC 402546736, HD 128898) around the harmonic of the principal mode – this is only the second case of such a phenomenon.
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Kurtz, D., and P. Martinez. "roAp stars." Highlights of Astronomy 10 (1995): 338–40. http://dx.doi.org/10.1017/s1539299600011461.

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Among the A stars there is a subclass of peculiar stars, the Ap stars, which show strongly enhanced spectral lines of the Fe peak, rare earth and lanthanide elements. These stars have global surface magnetic fields several orders of magnitude larger than that of the Sun, 0.3 to 30 kGauss is the measured range. For stars with the strongest magnetic fields, the spectral lines are split by the Zeeman Effect and the surface magnetic field strength can be measured. Generally, though, the magnetic fields are not strong enough for the magnetic splitting to exceed other sources of line broadening. In these cases residual polarization differences between the red and blue wings of the spectral lines give a measure of the effective magnetic field strength - the integral of the longitudinal component of the global magnetic field over the visible hemisphere, weighted by limb-darkening. In the Ap stars the effective magnetic field strengths vary with rotation. This is well understood in terms of the oblique rotator model in which the magnetic axis is oblique to the rotation axis, so that the magnetic field is seen from varying aspect with rotation.
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Matthews, Jaymie M. "Seismology of Pulsating Ap Stars: Results From The Past Decade, Prospects For The Next." International Astronomical Union Colloquium 139 (1993): 122–31. http://dx.doi.org/10.1017/s0252921100117087.

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AbstractSince the discovery of the first rapidly oscillating Ap (roAp) star in 1978 by Kurtz, this class of magnetic chemically-peculiar pulsators has grown to over two dozen. The eigenfrequency spectra of roAp stars (with periods of ∼ 6 – 15 min) are consistent with nonradial p- modes of low degree and high overtone n, not unlike the Sun's five-minute oscillations seen in integrated light. However, unlike the Sun, the strong global dipole fields of roAp stars significantly affect the pulsations.Although much of the effort in the last decade has been towards detecting new roAp candidates and refining the frequencies of known variables, initial “seismic” analyses have already yielded important results. Measurements of fundamental frequency spacings constrain the luminosities and radii of some roAp stars. In addition, mode splitting provides: (1) an independent determination of rotation period, even in the absence of longer-term light variations; (2) limits on the rotational inclination i and magnetic obliquity β; and (3) an indication of the relative internal field strengths of certain roAp stars. Very recently, the temperature - optical depth structure of the atmosphere of HR 3831 was inferred from optical and IR photometry of its oscillations.Judging from current developments, the next decade promises exciting results on both observational and theoretical fronts. Several roAp stars have now been monitored for over a decade, allowing us to investigate long-term period changes due to evolution, binarity, etc. Eigenfrequency models for stars in the mass and radius range appropriate for Ap stars are becoming available, as well as explicit treatments of the perturbations due to magnetic fields. Armed with these, we may be able to place some roAp stars on a theoretical (or “asteroseismological H-R“) diagram to derive independently their masses and main-sequence ages.
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Paris, Sophie, Jean-Paul Debeaupuis, Reto Crameri, Marilyn Carey, Franck Charlès, Marie Christine Prévost, Christine Schmitt, Bruno Philippe, and Jean Paul Latgé. "Conidial Hydrophobins of Aspergillus fumigatus." Applied and Environmental Microbiology 69, no. 3 (March 2003): 1581–88. http://dx.doi.org/10.1128/aem.69.3.1581-1588.2003.

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ABSTRACT The surface of Aspergillus fumigatus conidia, the first structure recognized by the host immune system, is covered by rodlets. We report that this outer cell wall layer contains two hydrophobins, RodAp and RodBp, which are found as highly insoluble complexes. The RODA gene was previously characterized, and ΔrodA conidia do not display a rodlet layer (N. Thau, M. Monod, B. Crestani, C. Rolland, G. Tronchin, J. P. Latgé, and S. Paris, Infect. Immun. 62:4380-4388, 1994). The RODB gene was cloned and disrupted. RodBp was highly homologous to RodAp and different from DewAp of A. nidulans. ΔrodB conidia had a rodlet layer similar to that of the wild-type conidia. Therefore, unlike RodAp, RodBp is not required for rodlet formation. The surface of ΔrodA conidia is granular; in contrast, an amorphous layer is present at the surface of the conidia of the ΔrodA ΔrodB double mutant. These data show that RodBp plays a role in the structure of the conidial cell wall. Moreover, rodletless mutants are more sensitive to killing by alveolar macrophages, suggesting that RodAp or the rodlet structure is involved in the resistance to host cells.
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Balona, L. A., D. L. Holdsworth, and M. S. Cunha. "High frequencies in TESS A–F main-sequence stars." Monthly Notices of the Royal Astronomical Society 487, no. 2 (May 23, 2019): 2117–32. http://dx.doi.org/10.1093/mnras/stz1423.

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Abstract The driving mechanism for high-frequency oscillations in some chemically peculiar Ap stars, the rapidly oscillating Ap stars (roAp stars), is not understood. The Transiting Exoplanet Survey Satellite mission (TESS) data provide an ideal opportunity to extend the number of roAp stars that might provide further clues to address this problem. From an examination of over 18 000 stars in TESS sectors 1–7, we have discovered high-frequency pulsations in 14 A–F stars, of which only 3 are classified as Ap stars. In addition to these new discoveries, we discuss the frequencies in nine previously known roAp stars. In one of these stars, HD 60435, we confirm a previous finding that the pulsations have lifetimes of only a few days. In another known roAp star, HD 6532, the relative amplitudes of the rotationally modulated sidelobes, which are generally used to estimate the inclination of the magnetic axis relative to the rotational axis, are significantly different from those found in ground-based B-band photometric observations. We also discuss four δ Scuti stars that appear to have independent frequencies similar to those of roAp stars.
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Martinez, Peter, and D. W. Kurtz. "Rapid Pulsations in Ap Stars." International Astronomical Union Colloquium 155 (1995): 58–69. http://dx.doi.org/10.1017/s0252921100036782.

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AbstractThe rapidly oscillating Ap (roAp) stars are upper mainsequence stars that pulsate in non-radial p modes of high overtone. We present an observer’s overview of the roAp phenomenon and discuss significant developments since the last major observational reviews of Kurtz (1990a) and Matthews (1991).
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Cunha, M. S., J. M. M. B. Fernandes, and M. J. P. F. G. Monteiro. "Seismic Tests of Theoretical Models of HR 1217." International Astronomical Union Colloquium 185 (2002): 302–3. http://dx.doi.org/10.1017/s0252921100016316.

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A way in which we might learn about the physics of the interior of roAp stars is by studying their oscillations. To that aim we have initiated a study in order to investigate what additional constraints might be imposed to the physics of the interior of roAp stars from the study of their oscillation spectra. We have chosen to start this work by studying the well known multi-periodic roAp star HR 1217. The observed data used for HR1217 were L/L⊙=7.8±0.7 and Teff=7400±100 K, from Matthews et al. (1999), Zs=0.009 estimated from Ryabchikova et al. (1997), and Δv=67.91±0.12μHz from Kurtz et al. (1989).
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Holdsworth, Daniel L., Hideyuki Saio, and Donald W. Kurtz. "HD 42659: the only known roAp star in a spectroscopic binary observed with B photometry, TESS, and SALT." Monthly Notices of the Royal Astronomical Society 489, no. 3 (September 2, 2019): 4063–71. http://dx.doi.org/10.1093/mnras/stz2419.

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ABSTRACT We present a multi-instrument analysis of the rapidly oscillating Ap (roAp) star HD 42659. We have obtained B photometric data for this star and use these data, in conjunction with the Transiting Exoplanet Survey Satellite (TESS) observations, to analyse the high-frequency pulsation in detail. We find a triplet that is split by the rotation frequency of the star (νrot = 0.3756 d−1; Prot = 2.66 d) and present both distorted dipole and distorted quadrupole mode models. We show that the pulsation frequency, 150.9898 d−1 (Ppuls = 9.54 min), is greater than the acoustic cut-off frequency. We utilize 27 high-resolution ($R\simeq 65\, 000$), high signal-to-noise ratio (∼120) spectra to provide new orbital parameters for this, the only known roAp star to be in a short-period binary (Porb = 93.266 d). We find the system to be more eccentric than previously thought, with e = 0.317, and suggest the companion is a mid-F to early-K star. We find no significant trend in the average pulsation mode amplitude with time, as measured by TESS, implying that the companion does not have an effect on the pulsation in this roAp star. We suggest further photometric observations of this star, and further studies to find more roAp stars in close binaries to characterize how binarity may affect the detection of roAp pulsations.
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Dissertations / Theses on the topic "ROABP"

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Medupe, Rodney. "Atmospheric temperature structure in the RoAp stars." Master's thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/18483.

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The rapidly oscillating Ap (roAp) stars are a sub-group of the chemically peculiar stars of class 2 (CP2), which are characterised by peculiar spectra and anomalously strong lines of Sr, Cr, Eu and other rare earth elements. They have strong global dipole magnetic fields with effective strengths of up to a few thousand gausses. Stars showing these phenomena cover the spectral range B8p to F0 V-IV. About 20 years ago rapid non-radial pulsations were discovered in the coolest members of the CP2 group, namely the roAp stars. These pulsations are due to high over-tone, low degree p modes with periods between 5.6 and 15 minutes. Since then, studies of these rapid oscillations have revealed a lot of information about these stars. The eigenfrequency spectra of roAp stars can potentially reveal information such as their rotation periods, rotational inclinations, magnetic geometries, internal magnetic field strengths, radii, masses, luminosities and ages. Matthews et al. (1990, 1996) suggested a technique to empirically determine the T(Ƭ) relation for roAp stars. This technique involves comparing the pulsation amplitudes obtained from multi-colour photometry to the ones calculated from black-body pulsator models (assuming dipole mode pulsations). This comparison yielded limb-darkening coefficients which were used to determine T(Ƭ) in a way similar to what was done for the sun. Matthews et al. based their idea on the observed fact that pulsation amplitudes of roAp stars drop sharply with increasing wavelength. They thus explained this sharp decline of amplitude with wavelength in terms of the strongly wavelength dependent limb-darkening. The initial aim of this thesis was to investigate the technique proposed by Matthews et al., and to apply it to a number of roAp stars. However, when a linearised expression for the variation of the pulsation amplitude with wavelength, limb-darkening, inclination of the pulsation axis α, and ΔT/T₀ (where ΔT is the polar pulsational temperature semi-amplitude and T₀ is the atmospheric temperature) was derived, it was discovered that limb-darkening is too small an effect to account for the observed amplitudes. The result is based on the Wien approximation and uses the Planck function to represent intensity. Therefore, limb-darkening cannot be measured from the amplitude vs wavelength data. This analysis and the results thereof are reported in this thesis. Numerical models based on realistic treatment of the intensity spectra (obtained from model atmospheres) are used to confirm and refine the analytical results. The linearised expression mentioned above suggests that an important factor that explains the sharp decline of amplitude with wavelength is the variation of the ratio ΔT/T₀ with wavelength. Therefore, if the T(Ƭ) structure of a star is known a priori (from model atmospheres), the variation of ΔT with wavelength can be determined. This new technique, together with the variation of opacity with wavelength in the atmospheres of roAp stars, is applied to HD 134214:, HD 137949, HD 128898, HD 101065 and HR 3831 to determine ΔT cos α as a function of atmospheric depth. HR 3831 was observed at various rotation phases to investigate the effect of rotation on the derived ΔT cos α vs atmospheric depth relation. Preliminary results on this are included in this thesis. Bibliography: pages 107-113.
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Pinheiro, Fernando Jorge Gutiérrez. "Oscillations in roAp and & Scuti Stars : Theory and observations." Master's thesis, Universidade do Porto. Reitoria, 1999. http://hdl.handle.net/10216/9689.

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Dissertação de Mestrado em Astronomia apresentada à Faculdade de Ciências da Universidade do Porto
As estrelas d Scuti e as estrelas roAp encontram-se na região da Faixa de Instabilidade das Cefeides que é atravessada pela Sequência principal. Cada tipo de estrelas apresenta frequências de oscilação que o outro género de estrelas não apresenta. Estas oscilações dependem da estrutura das estrelas, e podem ser descritas pelos modelos apropriados.De modo inverso, podemos a partir de observações obter as características de uma estrela, usando os modelos adequados.Discutiremos os modos de obter e reduzir observações dessas estrelas, e de analisar os dados obtidos com o objectivo de encontrar essas frequências de oscilação. Em particular tentaremos descobrir quis são as condições necessárias para se obter algumas características das estrelas BN Cnc e BV Cnc do enxame do Presépio (M44) na constelação do Caranguejo.
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Pinheiro, Fernando Jorge Gutiérrez. "Oscillations in roAp and & Scuti Stars : Theory and observations." Dissertação, Universidade do Porto. Reitoria, 1999. http://hdl.handle.net/10216/9689.

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Dissertação de Mestrado em Astronomia apresentada à Faculdade de Ciências da Universidade do Porto
As estrelas d Scuti e as estrelas roAp encontram-se na região da Faixa de Instabilidade das Cefeides que é atravessada pela Sequência principal. Cada tipo de estrelas apresenta frequências de oscilação que o outro género de estrelas não apresenta. Estas oscilações dependem da estrutura das estrelas, e podem ser descritas pelos modelos apropriados.De modo inverso, podemos a partir de observações obter as características de uma estrela, usando os modelos adequados.Discutiremos os modos de obter e reduzir observações dessas estrelas, e de analisar os dados obtidos com o objectivo de encontrar essas frequências de oscilação. Em particular tentaremos descobrir quis são as condições necessárias para se obter algumas características das estrelas BN Cnc e BV Cnc do enxame do Presépio (M44) na constelação do Caranguejo.
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Medupe, Rodney. "Studies of non-adiabatic pulsations in the atmospheres of the roAp stars." Doctoral thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/9582.

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Includes bibliographical references.
The roAp stars are high overtone pulsators characterised by strong global magnetic fields with effective field strength of between a few hundred to a few thousand Gauss. They also show overabundances in rare-earths and iron peak element. Multi-colour photometry of roAp stars shows that their pulsation amplitudes decrease more rapidly with increasing wavelength compared to other classically pulsating stars (e.g. Medupe & Kurtz 1998). In addition, this thesis shows that the pulsation phase can vary by up to 80° from Johnson U to V filters. In an attempt to explain the amplitude vs wavelength Kurtz & Medupe (1996) derived an analytic formula that indicated that the steep variation of the temperature eigenfunction with depth in the roAp atmospheres is the possible reason the rapid decrease of amplitude with wavelength. Even though Medupe & Kurtz (1998) showed that the analytical formula they derived in 1996 was a special form of a more general formula presented in Watson (1988), they found limitations in both formulae (see also Medupe, Christensen-Dalsgaard & Kurtz 1998 and chapter 3 of this thesis). This motivated me to attempt a numerical solution of the pulsation equations with consistent treatment of radiative transfer to investigate the multi-colour photometric data. In this thesis, we report on the multi-colour pulsation amplitudes and phases for HD 128898, HD 101065, HD 134214 and HD 137949. We also report on the campaign undertaken in 1996 and 1998 to determine whether the HR 3831 amplitude and phase vs wavelength changes with rotation. No variations with rotation are found. We find that the pulsation phase varies by up to about 80° from Johnson U to V in HD 101065 and HR 3831.
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V, Girish. "Search for Northern Hemisphere Rapidly Oscillating Ap stars." Thesis, Indian Institute of Science, 2005. http://hdl.handle.net/2005/101.

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Rapidly oscillating Ap (roAp) stars are cool, magnetic, chemically peculiar A-F type stars which exhibit high frequency oscillations similar to that of the famous five minute oscillations of Sun. These oscillations are interpreted as low degree (l<3), high order (n >10-30), non-radial p-mode oscillations. The periods of these pulsations lie in the range of 4-16 minutes with typical amplitudes of few milli-magnitudes (< 8mmag) in the Johnson-B filter. More than a dozen roAp stars are multiperiodic, making them suitable for asteroseismology. The presence of high magnetic fields (of the order of few kG) in these stars gives us a chance to study the effects of magnetic fields on pulsations. The thesis presents the efforts to search for new roAp stars in the northern hemisphere and its results.
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V, Girish. "Search for Northern Hemisphere Rapidly Oscillating Ap stars." Thesis, Indian Institute of Science, 2004. https://etd.iisc.ac.in/handle/2005/101.

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Rapidly oscillating Ap (roAp) stars are cool, magnetic, chemically peculiar A-F type stars which exhibit high frequency oscillations similar to that of the famous five minute oscillations of Sun. These oscillations are interpreted as low degree (l<3), high order (n >10-30), non-radial p-mode oscillations. The periods of these pulsations lie in the range of 4-16 minutes with typical amplitudes of few milli-magnitudes (< 8mmag) in the Johnson-B filter. More than a dozen roAp stars are multiperiodic, making them suitable for asteroseismology. The presence of high magnetic fields (of the order of few kG) in these stars gives us a chance to study the effects of magnetic fields on pulsations. The thesis presents the efforts to search for new roAp stars in the northern hemisphere and its results.
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Bigot, Lionel. "Astérosismologie des étoiles roAp : effets du champ magnétique et de la rotation sur les oscillations." Université Joseph Fourier (Grenoble), 2002. http://www.theses.fr/2002GRE10001.

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Nair, Vineet. "Expanders in Arithmetic Circuit Lower Bound : Towards a Separation Between ROABPs and Multilinear Depth 3 Circuits." Thesis, 2015. https://etd.iisc.ac.in/handle/2005/4811.

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Consider the problem of Polynomial Identity Testing(PIT): we are given an arithmetic circuit computing a multivariate polynomial over some eld and we have to determine whether that polynomial is identically zero or not. PIT is a fundamental problem and has applications in both algorithms and complexity theory. In this work, our aim is to study PIT for the model of multilinear depth three circuits for which no deterministic polynomial time identity test is known. An nO(log n) time blackbox PIT for set-multilinear depth three circuits (a special kind of multilinear depth three circuits) is known due to [ASS12], [FS13]. To get a better understanding of the problem at hand, we move towards multilinear depth three circuits by considering in- termediate circuit classes which encompasse more polynomials than set-multilinear depth three circuits and are `natural' subclasses of multilinear depth three circuits. One such model is `superposition of set-multilinear depth 3 circuits'. Our initial observations are: There is an nO(log n) whitebox PIT for superposition of two set-multilinear depth 3 circuits. There is a sub-exponential time whitebox PIT for superposition of constantly many set- multilinear depth 3 circuits. The second observation is subsumed by the recent independent and almost simultaneous work by [OSV15] that gives sub-exponential time hitting set for multilinear depth three circuits. A recent line of research considers hitting set for Read Once Oblivious Algebraic Branching Programs (ROABP's) which subsumes set-multilinear depth three circuits. An nO(log n) black box PIT is given for ROABP's of width polynomial in the number of variables in [AGKS14]. It is natural to ask whether this result on ROABP PIT can be used to give e cient (meaning polynomial or quasi-polynomial time) PIT for multilinear depth three circuits. For instance, the result by [OSV15] elegantly uses ROABP PIT as a `base case' (in a certain sense) to give a sub-exponential time PIT algorithm for multilinear depth three circuits. At this point, we wondered if multilinear depth three circuits of size s could also be computed by an ROABP of size polynomial in s. If true then this would immediately imply a quasi-polynomial time hitting set for multilinear depth three circuits, which is a long standing open problem in algebraic complexity theory. For instance, it can be shown that any multlinear depth three circuit with top fan-in two and just two variables per linear polynomial can be computed by an ROABP with constant width. But we show in our main result that this is not true for general multilinear depth three circuits that are superpositions of only two set-multilinear depth three circuits. There is a polynomial computed by a superposition of two set-multilinear depth 3 circuits with top fan-in just three and size polynomial in the number of variables n, such that any ROABP computing the polynomial has width 2 (n). There is a polynomial computed by a superposition of three set-multilinear depth 3 circuits with top fan-in just two and size polynomial in the number of variables n, such that any ROABP computing the polynomial has width 2 (n). This means the approach of directly converting a multilinear depth 3 circuit (even a superposi- tion of set-multilinear depth 3 circuits) to an ROABP and then applying the existing PIT for ROABP will not work. However the underlying techniques in [ASS12], [AGKS14] and [OSV15] might still be useful. The proofs of the above lower bounds are based on explicit construction of expander graphs that can be used to design multilinear depth three circuits (in particular su- perposition of set-multilinear depth 3 circuits) with high `evaluation dimension' - a complexity measure that is well suited to capture a `weakness' of ROABPs.
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Chagnon, François. "Searching for northern roap stars: the UBC-OAN photometric survey." Thesis, 1998. http://hdl.handle.net/2429/8021.

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Because they pulsate in multiple high-overtone p-modes, rapidly oscillating Ap stars (roAp) represent a very powerful tool to apply the techniques of asteroseismology, which can lead to the global properties and internal structure of stars. The majority of roAp stars are in the Southern Hemisphere, beyond the reach of northern observatories like CFHT and DAO, which have superb coude spectrographs that can help reveal additional modes and clues to the pulsation dynamics. To try to correct this imbalance, we began a systematic search for roAp stars in the Northern Hemisphere. The UBC-OAN roAp star Survey was conducted with the 84-cm and 1.5-m telescopes at the Observatorio Astronomico Nacional (OAN) in Mexico, equipped with a single-channel photoelectric photometer and a Johnson B filter. During 28 nights in July/August 1997 and 16 nights in May/June 1998, we monitored about 50 cool A-Fp stars with time resolution of less than a minute. The reduced data were Fourier analysed to search for periodic signals and we were generally sensitive to amplitudes as small as 0.3 millimagnitude in the period range of 4-15 min. We have made one detection, HD 10088, which shows two periods near 9.3 and 10.6 min, and amplitudes of about 1.6 and 1.3 mmag respectively, at the 99% confidence level. A tentative candidate, HD 3883, with period near 9.2 min and amplitude around 1.35 mmag is highlighted for further study. We also observed the known roAp star 10 Aql (HD 176232) and detected its main pulsation at a period near 11.5 min, the largest amplitude yet observed for this star. Finally, we independently confirm the newly discovered roAp star HD 122970 (Handler & Paunzen 1998) and combine our data with those of a global campaign (Handler et al. 1998) to infer some of the characteristics of this star.
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Books on the topic "ROABP"

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Bag lady or powerhouse?: A roaap for midlife (boomer) women. Calgary: Detselig Enterprises, 2009.

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Separat︠s︡ii︠a︡ i individuat︠s︡ii︠a︡ lichnostʹ i semʹ︠i︡a: Materialy VIII i IX konferent︠s︡iĭ MAAP, ROAP i RGAP SPb. Sankt-Peterburg: Skifii︠a︡ print, 2010.

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Robby, Tulus, International Co-operative Alliance. Regional Office for Asia & the Pacific., and National Confederation of Cooperatives, eds. Coop resilience in the face of the economic crisis: Excerpts from the ICA ROAP think tank consortium. New Delhi: The Regional Office, 1998.

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ICA ROAP Sub-Regional Workshop on Gender Integration in Co-operatives (1st 1995 Kuala Lumpur, Malaysia). Report of the ICA ROAP Sub-Regional Workshop on Gender Integration in Co-operatives: I, 18-22 August, 1995, Kuala Lumpur, Malaysia, II, 15-20 April, 1996, Pune, India. New Delhi, India: International Co-operative Alliance, Regional Office for Asia and the Pacific, 1996.

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Ireland Touring Roap Map. Hammond World Atlas Corp, 1995.

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Report of the ICA ROAP Sub-Regional Workshop on Gender Integration in Co-operatives: I, 18-22 August, 1995, Kuala Lumpur, Malaysia, II, 15-20 April, 1996, Pune, India. International Co-operative Alliance, Regional Office for Asia and the Pacific, 1996.

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Book chapters on the topic "ROABP"

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Kurtz, D. W. "An Introduction to Ap Stars, roAp Stars and the Asteroseismology of roAp Stars." In Variable Stars as Essential Astrophysical Tools, 313–38. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4299-1_12.

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Matthews, Jaymie M. "Probing the Interiors of Roap Stars." In Sounding Solar and Stellar Interiors, 387–94. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5163-4_33.

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3

Hatzes, A. P., D. E. Mkrtichian, and A. Kanaan. "Pulsational Radial Velocity Studies of Roap Stars." In Variable Stars as Essential Astrophysical Tools, 397–404. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4299-1_17.

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4

Gautschy, Alfred, and Hideyuki Saio. "RoAp Stars Through Theorists’ Eyes — Excitation Mechanism." In New Eyes to See Inside the Sun and Stars, 277–84. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-4982-2_60.

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Audard, N., F. Kupka, W. W. Weiss, P. Morel, and J. Provost. "The Acoustic Cut-Off Frequency of roAp Stars." In New Eyes to See Inside the Sun and Stars, 299–300. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-4982-2_64.

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Bigot, L., and W. A. Dziembowski. "Are Pulsation and Magnetic Axes Aligned in roAP Stars?" In Asteroseismology Across the HR Diagram, 217–20. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-0799-2_27.

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Kurtz, D. W. "Long-Term Monitoring of Cyclic Frequency Variability in roAp Stars." In Variable Stars as Essential Astrophysical Tools, 363–72. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4299-1_14.

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Kurtz, D. W. "Multi-Color Observations and Atmospheric Level Effects in roAp Stars." In Variable Stars as Essential Astrophysical Tools, 373–86. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4299-1_15.

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9

Baldry, I. K., T. R. Bedding, M. Viskum, H. Kjeldsen, and S. Frandsen. "Bisector Velocities of Hα in the roAp Star α Cir." In New Eyes to See Inside the Sun and Stars, 309–10. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-4982-2_66.

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Kurtz, D. W. "Present Observational Status of the Intermediate Mass Stars: δ Sct Stars, γ Dor Stars and roAp Stars." In Asteroseismology Across the HR Diagram, 29–35. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-0799-2_5.

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Conference papers on the topic "ROABP"

1

Kurtz, D. W., L. M. Freyhammer, V. G. Elkin, G. Mathys, Richard J. Stancliffe, Guenter Houdek, Rebecca G. Martin, and Christopher A. Tout. "Discoveries in the Atmospheres of roAp Stars." In UNSOLVED PROBLEMS IN STELLAR PHYSICS: A Conference in Honor of Douglas Gough. AIP, 2007. http://dx.doi.org/10.1063/1.2818978.

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Nomura, T., H. Shibahashi, Joyce Ann Guzik, and Paul A. Bradley. "Numerical Simulation of Line Profile Variation in roAp Stars." In STELLAR PULSATION: CHALLENGES FOR THEORY AND OBSERVATION: Proceedings of the International Conference. AIP, 2009. http://dx.doi.org/10.1063/1.3246552.

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Saio, Hideyuki, Tanya Ryabchikova, Mikhail Sachkov, Joyce Ann Guzik, and Paul A. Bradley. "Modelling the Pulsations of the roAp Star HR 1217." In STELLAR PULSATION: CHALLENGES FOR THEORY AND OBSERVATION: Proceedings of the International Conference. AIP, 2009. http://dx.doi.org/10.1063/1.3246554.

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Yoon, Eun-Jun, Jeung-Seop Kim, Byung-Ho Cho, and Kee-Young Yoo. "Efficient OMA DRM v2.0 ROAP for Protecting a Rights Object for a Device." In 2008 Second International Conference on Future Generation Communication and Networking Symposia (FGCNS). IEEE, 2008. http://dx.doi.org/10.1109/fgcns.2008.82.

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You might also be interested in the extended bibliographies on the topic 'ROABP' for particular source types:
Journal articles
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