Discovery and Timing Analysis of New Pulsars in Globular Cluster NGC 5024: New Observations from FAST by Yujie Lian, Zhichen Pan, Haiyan Zhang, P. C. C. Freire, Shuo Cao, Lei Qian

“…The companions, with masses of 0.25, 0.27, and 0.18 M _⊙ , respectively, are likely to be white dwarf stars; if they are extended objects, they do not eclipse the pulsars. …”
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A Brown Dwarf Companion to the Nova-like Variable RW Tri by Zhibin Dai, Shengbang Qian, Indika Medagangoda

“…The orbital period of Nova-like variable RW Tri is expected to experience a long-term evolution due to a stable mass transfer from the red dwarf to the white dwarf. By adding 297 new eclipse timings obtained from our own observations and a cross-identification of many databases, we fully reinvestigated the variations in orbital period of RW Tri, based on a total of 658 data points spanning over 80 years. …”
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The GW Vir Instability Strip in Light of New Observations of PG 1159 Stars: Discovery of Pulsations in the Central Star of A72 and Variability of RX J0122.9–7521 by Paulina Sowicka, Gerald Handler, David Jones, John A. R. Caldwell, Francois van Wyk, Ernst Paunzen, Karolina Bąkowska, Luis Peralta de Arriba, Lucía Suárez-Andrés, Klaus Werner, Marie Karjalainen, Daniel L. Holdsworth

“…We present the results of new time-series photometric observations of 29 pre–white dwarf stars of PG 1159 spectral type, carried out in the years 2014–2022. …”
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Weakened Magnetic Braking in the Exoplanet Host Star 51 Peg by Travis S. Metcalfe, Klaus G. Strassmeier, Ilya V. Ilyin, Derek Buzasi, Oleg Kochukhov, Thomas R. Ayres, Sarbani Basu, Ashley Chontos, Adam J. Finley, Victor See, Keivan G. Stassun, Jennifer L. van Saders, Aldo G. Sepulveda, George R. Ricker

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Ultradeep ATCA Imaging of 47 Tucanae Reveals a Central Compact Radio Source by Alessandro Paduano, Arash Bahramian, James C. A. Miller-Jones, Adela Kawka, Tim J. Galvin, Liliana Rivera Sandoval, Sebastian Kamann, Jay Strader, Laura Chomiuk, Craig O. Heinke, Thomas J. Maccarone, Stefan Dreizler

“…We use radio, X-ray, optical, and UV data to show that explanations involving a background active galactic nucleus, a chromospherically active binary, or a binary involving a white dwarf are unlikely. The most plausible explanations are that the source is an undiscovered millisecond pulsar or a weakly accreting black hole. …”
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CHANDRA AND SUZAKU OBSERVATIONS OF THE Be/X-RAY STAR HD110432 by Torrejon, J. M., Schulz, Norbert S., Nowak, Michael A.

“…The analysis of the Si XIII and S XV He-like triplets present in the Chandra spectrum points to a very dense (n[subscript e] ~ 10[superscript 13] cm[superscript –3]) plasma located either close to the stellar surface (r < 3R [subscript *]) of the Be star or, alternatively, very close (r ~ 1.5R [subscript WD]) to the surface of a (hypothetical) white dwarf companion. We argue, however, that the available data support the first scenario.…”
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High-cadence Timing of Binary Pulsars with CHIME by Chia Min Tan, Emmanuel Fonseca, Kathryn Crowter, Fengqiu Adam Dong, Victoria M. Kaspi, Kiyoshi W. Masui, James W. McKee, Bradley W. Meyers, Scott M. Ransom, Ingrid H. Stairs

“…The binary companion to PSR J2023+2853 was found to have a mass of ${0.93}_{-0.14}^{+0.17}$ M _⊙ ; in the context of the near-circular orbit, this mass estimate suggests that the companion to PSR J2023+2853 is likely a high-mass white dwarf. By comparing the timing model obtained for PSR J0218+4232 with previous observations, we found a significant change in the observed orbital period of the system of $\dot{{P}_{{\rm{b}}}}=0.14(2)\times {10}^{-12}$ ; we determined that this variation arises from “Shklovskii acceleration” due to the relative motion of the binary system, and used this measurement to estimate a distance of d = (6.7 ± 1.0) kpc to PSR J0218+4232. …”
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The Fast X-Ray Transient XRT 210423 and Its Host Galaxy by D. Eappachen, P. G. Jonker, A. J. Levan, J. Quirola-Vásquez, M. A. P. Torres, F. E. Bauer, V. S. Dhillon, T. Marsh, S. P. Littlefair, M. E. Ravasio, M. Fraser

“…Possible origins include the tidal disruption of a white dwarf by an intermediate-mass black hole, a supernova shock breakout, or a binary neutron star merger. …”
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Constraints on Magnetic Braking from the G8 Dwarf Stars 61 UMa and τ Cet by Travis S. Metcalfe, Klaus G. Strassmeier, Ilya V. Ilyin, Jennifer L. van Saders, Thomas R. Ayres, Adam J. Finley, Oleg Kochukhov, Pascal Petit, Victor See, Keivan G. Stassun, Sandra V. Jeffers, Stephen C. Marsden, Julien Morin, Aline A. Vidotto

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The Common Envelope Evolution Outcome. II. Short-orbital-period Hot Subdwarf B Binaries Reveal a Clear Picture by Hongwei Ge, Christopher A Tout, Ronald F Webbink, Xuefei Chen, Arnab Sarkar, Jiao Li, Zhenwei Li, Lifu Zhang, Zhanwen Han

“…Short-orbital-period hot subdwarf B star (sdB) plus white dwarf (WD) binaries are the most straightforward samples with which to constrain CEE physics. …”
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Value-added Catalog of M-giant Stars in LAMOST DR9 by Jing Li, Lin Long, Jing Zhong, Lin Tang, Bo Zhang, Songmei Qin, Yirong Chen, Zhengzhou Yan, Li Chen, Xiang-Xiang Xue, Jinliang Hou, Jian-Rong Shi

“…The 2471 misclassified non–M-giant stars are white dwarf binaries, early types, and M dwarfs. And the contamination rate is 4.2% in the M-giants sample. …”
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SN 2020uem: a Possible Thermonuclear Explosion within a Dense Circumstellar Medium (II). The Properties of the CSM from Polarimetry and Light-curve Modeling by Kohki Uno, Takashi Nagao, Keiichi Maeda, Hanindyo Kuncarayakti, Masaomi Tanaka, Koji S. Kawabata, Tatsuya Nakaoka, Miho Kawabata, Masayuki Yamanaka, Kentaro Aoki, Keisuke Isogai, Mao Ogawa, Akito Tajitsu, Ryo Imazawa

“…As a possible progenitor scenario of SN 2020uem, we propose a white dwarf binary system including an RG, RSG, or AGB star, especially a merger scenario via common envelope evolution, i.e., the core-degenerate scenario or a variant.…”
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Missing for 20 yr: MeerKAT Redetects the Elusive Binary Pulsar M30B by Vishnu Balakrishnan, Paulo C. C. Freire, S. M. Ransom, Alessandro Ridolfi, E. D. Barr, W. Chen, Vivek Venkatraman Krishnan, D. Champion, M. Kramer, T. Gautam, Prajwal V. Padmanabh, Yunpeng Men, F. Abbate, B. W. Stappers, I. Stairs, E. Keane, A. Possenti

“…The massive, undetected companion could either be a massive white dwarf or a neutron star. M30B likely formed as a result of a secondary exchange encounter. …”
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The Luminous Type Ia Supernova 2022ilv and Its Early Excess Emission by Shubham Srivastav, S. J. Smartt, M. E. Huber, G. Dimitriadis, K. C. Chambers, Michael D. Fulton, Thomas Moore, F. P. Callan, James H. Gillanders, K. Maguire, M. Nicholl, Luke J. Shingles, S. A. Sim, K. W. Smith, J. P. Anderson, Thomas de Boer, Ting-Wan Chen, Hua Gao, D. R. Young

“…This may be realized in a double-degenerate scenario, wherein a white dwarf merger is preceded by the ejection of a small amount (∼10 ^−3 –10 ^−2 M _⊙ ) of hydrogen and helium-poor tidally stripped material. …”
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The RS Oph Outburst of 2021 Monitored in X-Rays with NICER by Marina Orio, Keith Gendreau, Morgan Giese, Gerardo Juan M. Luna, Jozef Magdolen, Tod E. Strohmayer, Andy E. Zhang, Diego Altamirano, Andrej Dobrotka, Teruaki Enoto, Elizabeth C. Ferrara, Richard Ignace, Sebastian Heinz, Craig Markwardt, Joy S. Nichols, Michael L. Parker, Dheeraj R. Pasham, Songpeng Pei, Pragati Pradhan, Ron Remillard, James F. Steiner, Francesco Tombesi

“…The central supersoft X-ray source (SSS), namely the shell hydrogen burning white dwarf (WD), became visible in the fourth week, initially with short flares. …”
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Over 500 Days in the Life of the Photosphere of the Type Iax Supernova SN 2014dt by Yssavo Camacho-Neves, Saurabh W. Jha, Barnabas Barna, Mi Dai, Alexei V. Filippenko, Ryan J. Foley, Griffin Hosseinzadeh, D. Andrew Howell, Joel Johansson, Patrick L. Kelly, Wolfgang E. Kerzendorf, Lindsey A. Kwok, Conor Larison, Mark R. Magee, Curtis McCully, John T. O’Brien, Yen-Chen Pan, Viraj Pandya, Jaladh Singhal, Benjamin E. Stahl, Tamás Szalai, Meredith Wieber, Marc Williamson

“…Type Iax supernovae (SNe Iax) are the largest known class of peculiar white dwarf SNe, distinct from normal Type Ia supernovae (SNe Ia). …”
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SN 2020udy: A New Piece of the Homogeneous Bright Group in the Diverse Iax Subclass by Mridweeka Singh, Devendra K. Sahu, Barnabás Barna, Anjasha Gangopadhyay, Raya Dastidar, Rishabh Singh Teja, Kuntal Misra, D. Andrew Howell, Xiaofeng Wang, Jun Mo, Shengyu Yan, Daichi Hiramatsu, Craig Pellegrino, G. C. Anupama, Arti Joshi, K. Azalee Bostroem, Jamison Burke, Curtis McCully, Rama Subramanian V, Gaici Li, Gaobo Xi, Xin Li, Zhitong Li, Shubham Srivastav, Hyobin Im, Anirban Dutta

“…Overall, the observational features of SN 2020udy are consistent with the deflagration of a carbon–oxygen white dwarf.…”
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Near-infrared and Optical Nebular-phase Spectra of Type Ia Supernovae SN 2013aa and SN 2017cbv in NGC 5643 by Sahana Kumar, Eric Y. Hsiao, C. Ashall, M. M. Phillips, N. Morrell, P. Hoeflich, C. R. Burns, L. Galbany, E. Baron, C. Contreras, S. Davis, T. Diamond, F. Förster, M. L. Graham, E. Karamehmetoglu, R. P. Kirshner, B. Koribalski, K. Krisciunas, J. Lu, G. H. Marion, P. J. Pessi, A. L. Piro, M. Shahbandeh, M. D. Stritzinger, N. B. Suntzeff, S. A. Uddin

“…The time evolution of the NIR [Fe ii ] 1.644 μ m line also indicates moderately high progenitor white dwarf central density and potentially high magnetic fields.…”
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SN 2022oqm–A Ca-rich Explosion of a Compact Progenitor Embedded in C/O Circumstellar Material by Ido Irani, Ping Chen, Jonathan Morag, Steve Schulze, Avishay Gal-Yam, Nora L. Strotjohann, Ofer Yaron, Erez A. Zimmerman, Amir Sharon, Daniel A. Perley, J. Sollerman, Aaron Tohuvavohu, Kaustav K. Das, Mansi M. Kasliwal, Rachel Bruch, Thomas G. Brink, WeiKang Zheng, Alexei V. Filippenko, Kishore C. Patra, Sergiy S. Vasylyev, Yi Yang, Matthew J. Graham, Joshua S. Bloom, Paolo Mazzali, Josiah Purdum, Russ R. Laher, Avery Wold, Yashvi Sharma, Leander Lacroix, Michael S. Medford

“…The early behavior can be explained by 10 ^−3 M _⊙ of optically thin circumstellar material (CSM) surrounding either (1) a massive compact progenitor such as a Wolf–Rayet star, (2) a massive stripped progenitor with an extended envelope, or (3) a binary system with a white dwarf. We propose that the early-time light curve is powered by both the interaction of the ejecta with the optically thin CSM and shock cooling (in the massive star scenario). …”
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The Green Bank North Celestial Cap Survey. VII. 12 New Pulsar Timing Solutions by J. K. Swiggum, Z. Pleunis, E. Parent, D. L. Kaplan, M. A. McLaughlin, I. H. Stairs, R. Spiewak, G. Y. Agazie, P. Chawla, M. E. DeCesar, T. Dolch, W. Fiore, E. Fonseca, A. G. Istrate, V. M. Kaspi, V. I. Kondratiev, J. van Leeuwen, L. Levin, E. F. Lewis, R. S. Lynch, A. E. McEwen, H. Al Noori, S. M. Ransom, X. Siemens, M. Surnis

“…We present timing solutions for 12 pulsars discovered in the Green Bank North Celestial Cap 350 MHz pulsar survey, including six millisecond pulsars (MSPs), a double neutron star (DNS) system, and a pulsar orbiting a massive white dwarf companion. Timing solutions presented here include 350 and 820 MHz Green Bank Telescope data from initial confirmation and follow-up, as well as a dedicated timing campaign spanning 1 ryr PSR J1122−3546 is an isolated MSP, PSRs J1221−0633 and J1317−0157 are MSPs in black widow systems and regularly exhibit eclipses, and PSRs J2022+2534 and J2039−3616 are MSPs that can be timed with high precision and have been included in pulsar timing array experiments seeking to detect low-frequency gravitational waves. …”
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