https://www.astronomerstelegram.org Neutron Star, from The Astronomer's Telegram en-us https://www.astronomerstelegram.org/?read=18089 Manoj Mandal, Sachindra Naik Manoj Mandal, Sachindra Naik manojmandal@prl.res.in Credentialed by: Manoj Mandal (manojmandal@prl.res.in) The Astronomer's Telegram ATel18089 We report preliminary timing and spectral results from the XPoSat/XSPECT observations of the Be/X-ray binary pulsar LS V +44 17 (RX J0440.9+4431) during its ongoing September 2026 X-ray outburst. ... 2026-10-04T09:02:31-00:00 https://www.astronomerstelegram.org/?read=18082 I. Mereminskiy, A. Semena, A. Lutovinov, S. Molkov, A. Tkachenko I. Mereminskiy, A. Semena, A. Lutovinov, S. Molkov, A. Tkachenko i.a.mereminskiy@gmail.com Credentialed by: Andrey Semena (san@iki.rssi.ru) The Astronomer's Telegram ATel18082 During the observations of the Galactic Plane on Sept. 28, 2026, the Mikhail Pavlinsky ART-XC telescope onboard the SRG observatory detected a bright X-ray source at the position of RA, Dec = 275.1232, -14.5692 (estimated 90% containment radius of 10''), with the observed X-ray flux in 4-12 keV of (7.9+-0.2)x10^-11 erg cm-2 s-1. ... 2026-09-29T13:22:42-00:00 https://www.astronomerstelegram.org/?read=18071 M. Nakajima, H. Negoro, T. Mihara, K. Saito, T. Yokoyama, M. Wada, T. Tamagawa, N. Kawai, M. Matsuoka, T. Sakamoto, M. Serino, S. Sugita, Y. Kawakubo, H. Hiramatsu, A. Yoshida, Y. Tsuboi, Y. Ishihara, H. Ogaki, M. Shidatsu, C. Kang, M. Uenishi, T. Usuki, S. Yatsuzuka, H. Aoe, I. Takahashi, Y. Yatsu, S. Nakahira, S. Ueno, H. Tomida, M. Kurihara, Y. Ueda, K. Fujiwara, S. Kobayashi, M. Yamauchi, M. Nishio, C. Hiraizumi, K. Yamaoka, M. Sugizaki, W. Iwakiri, T. Kawamuro, S. Yamada, S. Ogawa M. Nakajima, H. Negoro, T. Mihara, K. Saito, T. Yokoyama, M. Wada, T. Tamagawa, N. Kawai, M. Matsuoka, T. Sakamoto, M. Serino, S. Sugita, Y. Kawakubo, H. Hiramatsu, A. Yoshida, Y. Tsuboi, Y. Ishihara, H. Ogaki, M. Shidatsu, C. Kang, M. Uenishi, T. Usuki, S. Yatsuzuka, H. Aoe, I. Takahashi, Y. Yatsu, S. Nakahira, S. Ueno, H. Tomida, M. Kurihara, Y. Ueda, K. Fujiwara, S. Kobayashi, M. Yamauchi, M. Nishio, C. Hiraizumi, K. Yamaoka, M. Sugizaki, W. Iwakiri, T. Kawamuro, S. Yamada, S. Ogawa nakajima.motoki@nihon-u.ac.jp Credentialed by: Motoki Nakajima (nakajima.motoki@nihon-u.ac.jp) The Astronomer's Telegram ATel18071 We report on anomalous X-ray activity from the Be/X-ray binary pulsar LS V +44 17 (RX J0440.9+4431). This binary system, hosting a & sim;205 sec X-ray pulsar, had previously been suggested to have an orbital period of & sim;150 days, estimated from the recurrence intervals of a series of X-ray outbursts observed in 2010-2011 (Reig 2011; Tsygankov et al. ... 2026-09-22T13:10:54-00:00 https://www.astronomerstelegram.org/?read=18067 Peter Jenke, Colleen Wilson-Hodge, Christian Malacaria Peter Jenke, Colleen Wilson-Hodge, Christian Malacaria peter.a.jenke@nasa.gov Credentialed by: Peter Jenke (peter.a.jenke@nasa.gov) The Astronomer's Telegram ATel18067 The GBM Accreting Pulsar Project (GAPP) is detecting pulsations from the transient Be/X-ray binary RX J0440.9+4431 (LSV+44) starting September 17, 2026. ... 2026-09-21T20:22:38-00:00 https://www.astronomerstelegram.org/?read=18063 Tian-Yu Liu, K. R. Ni, S. Q. Zheng, Jin-Rui Liu, G. J. Yang, B. B. Zhang and Z.-X. Ling, on behalf of the Einstein Probe team: Tian-Yu Liu, K. R. Ni, S. Q. Zheng, Jin-Rui Liu, G. J. Yang, B. B. Zhang and Z.-X. Ling, on behalf of the Einstein Probe team: ep_ta@bao.ac.cn Credentialed by: Yuan Liu (liuyuan@bao.ac.cn) The Astronomer's Telegram ATel18063 We report on the detection of X-ray brightening, likely from LS V +44 17, by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission. ... 2026-09-20T18:56:46-00:00 https://www.astronomerstelegram.org/?read=18051 G. K. Jaisawal G. K. Jaisawal gaurava@space.dtu.dk Credentialed by: Gaurava Kumar Jaisawal (gaurava.jaisawal@gmail.com) The Astronomer's Telegram ATel18051 We report on a Swift/XRT observation of the Be/X-ray binary pulsar 1A 0538-66 following the trigger of a major X-ray outburst detected by MAXI/GSC on 2026 August 28 (ATel #18020). ... 2026-09-17T11:47:13-00:00 https://www.astronomerstelegram.org/?read=18040 Marcus E. Lower, Jade Salisbury, Ryan M. Shannon, Fernando Camilo, Paul Scholz, George Younes, John E. Reynolds and John M. Sarkissian Marcus E. Lower, Jade Salisbury, Ryan M. Shannon, Fernando Camilo, Paul Scholz, George Younes, John E. Reynolds and John M. Sarkissian mlower@swin.edu.au Credentialed by: Marcus Lower (mlower@swin.edu.au) The Astronomer's Telegram ATel18040 Following a reported X-ray burst from the direction of the magnetar XTE J1810-197 (PSR J1809-1943) by MAXI/GSC (ATel #18039), we triggered a search for renewed radio emission using the Ultra-Wideband Low (UWL; Hobbs et al. ... 2026-09-14T09:25:02-00:00 https://www.astronomerstelegram.org/?read=18039 H. Negoro, M. Serino, M. Nakajima, K. Saito, T. Yokoyama, M. Wada, T. Mihara, T. Tamagawa, N. Kawai, M. Matsuoka, T. Sakamoto, S. Sugita, Y. Kawakubo, H. Hiramatsu, A. Yoshida, Y. Tsuboi, Y. Ishihara, H. Ogaki, M. Shidatsu, C. Kang, M. Uenishi, T. Usuki, S. Yatsuzuka, H. Aoe, I. Takahashi, Y. Yatsu, S. Nakahira, S. Ueno, H. Tomida, M. Kurihara, Y. Ueda, K. Fujiwara, S. Kobayashi, M. Yamauchi, M. Nishio, C. Hiraizumi, K. Yamaoka, M. Sugizaki, W. Iwakiri, T. Kawamuro, S. Yamada, and S. Ogawa H. Negoro, M. Serino, M. Nakajima, K. Saito, T. Yokoyama, M. Wada, T. Mihara, T. Tamagawa, N. Kawai, M. Matsuoka, T. Sakamoto, S. Sugita, Y. Kawakubo, H. Hiramatsu, A. Yoshida, Y. Tsuboi, Y. Ishihara, H. Ogaki, M. Shidatsu, C. Kang, M. Uenishi, T. Usuki, S. Yatsuzuka, H. Aoe, I. Takahashi, Y. Yatsu, S. Nakahira, S. Ueno, H. Tomida, M. Kurihara, Y. Ueda, K. Fujiwara, S. Kobayashi, M. Yamauchi, M. Nishio, C. Hiraizumi, K. Yamaoka, M. Sugizaki, W. Iwakiri, T. Kawamuro, S. Yamada, and S. Ogawa negoro.hitoshi@nihon-u.ac.jp Credentialed by: Hitoshi Negoro (negoro@phys.cst.nihon-u.ac.jp) The Astronomer's Telegram ATel18039 MAXI/GSC detected bright X-ray burst-like activity lasting more than 30 sec at 12:43 UT on September 12, 2026. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (272.340 deg, -19.668 deg) = (18 09 22, -19 40 05 (J2000) with a statistical 90% C.L. ... 2026-09-12T16:49:24-00:00 https://www.astronomerstelegram.org/?read=18031 M. Nakajima, H. Negoro, M. Serino, S. Sugita, K. Saito, T. Yokoyama, M. Wada, T. Mihara, T. Tamagawa, N. Kawai, M. Matsuoka, T. Sakamoto, Y. Kawakubo, H. Hiramatsu, A. Yoshida, Y. Tsuboi, Y. Ishihara, H. Ogaki, M. Shidatsu, C. Kang, M. Uenishi, T. Usuki, S. Yatsuzuka, H. Aoe, I. Takahashi, Y. Yatsu, S. Nakahira, S. Ueno, H. Tomida, M. Kurihara, Y. Ueda, K. Fujiwara, S. Kobayashi, M. Yamauchi, M. Nishio, C. Hiraizumi, K. Yamaoka, M. Sugizaki, W. Iwakiri, T. Kawamuro, S. Yamada, S. Ogawa M. Nakajima, H. Negoro, M. Serino, S. Sugita, K. Saito, T. Yokoyama, M. Wada, T. Mihara, T. Tamagawa, N. Kawai, M. Matsuoka, T. Sakamoto, Y. Kawakubo, H. Hiramatsu, A. Yoshida, Y. Tsuboi, Y. Ishihara, H. Ogaki, M. Shidatsu, C. Kang, M. Uenishi, T. Usuki, S. Yatsuzuka, H. Aoe, I. Takahashi, Y. Yatsu, S. Nakahira, S. Ueno, H. Tomida, M. Kurihara, Y. Ueda, K. Fujiwara, S. Kobayashi, M. Yamauchi, M. Nishio, C. Hiraizumi, K. Yamaoka, M. Sugizaki, W. Iwakiri, T. Kawamuro, S. Yamada, S. Ogawa nakajima.motoki@nihon-u.ac.jp Credentialed by: Motoki Nakajima (nakajima.motoki@nihon-u.ac.jp) The Astronomer's Telegram ATel18031 The MAXI/GSC nova alert system triggered an X-ray transient source at (R.A., Dec) = (128 deg, -43 deg) on August 29, 2026 (MJD 61281). Since the source was observed during high-background orbits in late August, its position could not be precisely determined from those scans. ... 2026-09-06T08:02:19-00:00 https://www.astronomerstelegram.org/?read=18025 Robbie Webbe, Natalie A. Webb, Erwan Quintin, Laurent Michel Robbie Webbe, Natalie A. Webb, Erwan Quintin, Laurent Michel robbie.webbe@cnrs.fr Credentialed by: Robbie Webbe (robbie.webbe@cnrs.fr) The Astronomer's Telegram ATel18025 We report the detection of X-ray brightening from the source IGR J13020-6359 with the XMM-Newton X-ray telescope in the energy range 0.2-12.0 keV. On 7th August 2026 IGR J13020-6359 was observed in the field of view of an XMM-Newton observation, and the long-term variability was assessed using the multi-observatory STONKS pipeline. ... 2026-09-01T10:23:44-00:00