March 2023 - vsnet-newvar - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-newvar 9864] Re: Wils_SDSSJ075107.50+300628.4: likely superoutburst
by Taichi Kato 08 Mar '23

08 Mar '23

Re: Wils_SDSSJ075107.50+300628.4: likely superoutburst > Almost superoutburst-only object with a short supercycle. > Superoutburst? in 2022 Oct. Indeed very likely for both. Very few normal outbursts were recorded in ATLAS despite the short supercycle. YYYYMMDD(UT) mag observer 20230302.5894 <156c (Yutaka Maeda) 20230304.5793 <151c (Yutaka Maeda) 20230305.5957 144c (Yutaka Maeda) 20230306.3344 15.172o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230306.3550 15.124o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230306.6223 149:c (Yutaka Maeda)

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[vsnet-newvar 9863] Re: Gaia23azk
by Taichi Kato 08 Mar '23

08 Mar '23

Re: Gaia23azk No past activity in ASAS-SN/ATLAS. https://asas-sn.osu.edu/sky-patrol/coordinate/9c515a17-75cd-480d-98e9-f5a7c…

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[vsnet-newvar 9862] ASASSN-15cv bright outburst?
by Taichi Kato 08 Mar '23

08 Mar '23

ASASSN-15cv bright outburst? Short outburst in 2019. YYYYMMDD(UT) mag observer 20230303.978 <16.30C (Gary Poyner) 20230303.9795 <162cG (Masao Funada) 20230304.5094 <158c (Yutaka Maeda) 20230305.5258 <157c (Yutaka Maeda) 20230306.5525 148:cG (Yutaka Maeda)

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[vsnet-newvar 9861] Wils_SDSSJ075107.50+300628.4: likely superoutburst
by Taichi Kato 08 Mar '23

08 Mar '23

Wils_SDSSJ075107.50+300628.4: likely superoutburst Almost superoutburst-only object with a short supercycle. Superoutburst? in 2022 Oct. YYYYMMDD(UT) mag observer 20230302.5894 <156c (Yutaka Maeda) 20230304.5793 <151c (Yutaka Maeda) 20230305.5957 144c (Yutaka Maeda) 20230306.6223 149:c (Yutaka Maeda)

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[vsnet-newvar 9860] Re: Gaia23azk
by Taichi Kato 08 Mar '23

08 Mar '23

Re: Gaia23azk > Bright transient. What is it? Reddened nova? Emission line in the spectrum? YYYYMMDD(UT) mag observer 20230306.6405 15.094o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230306.6446 15.081o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230306.6519 15.044o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230306.6626 15.040o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230307.3733 14.790o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230307.3751 14.869o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230307.3917 14.823o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505))

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[vsnet-newvar 9859] Gaia23azk
by Taichi Kato 07 Mar '23

07 Mar '23

Gaia23azk Bright transient. What is it? http://gsaweb.ast.cam.ac.uk/alerts/alert/Gaia23azk/ Gaia23azk AT2023ctx 2023-03-05 12:55:35 286.80714 9.48159 13.85 unknown 2023-03-07 12:49:08 Apparently hostless red transient

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[vsnet-newvar 9858] Gaia23azp
by Taichi Kato 07 Mar '23

07 Mar '23

Gaia23azp http://gsaweb.ast.cam.ac.uk/alerts/alert/Gaia23azp/ Gaia23azp AT2023ctz 2023-03-05 16:51:35 300.10042 19.99443 15.33 20.53 0.13 unknown 2023-03-07 12:51:14 ~5 mag outburst in Gaia source

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[vsnet-newvar 9857] ASASSN-14aj likely superoutburst
by Taichi Kato 07 Mar '23

07 Mar '23

ASASSN-14aj likely superoutburst Known SU UMa star. YYYYMMDD(UT) mag observer 20230302.8076 <149c (Yutaka Maeda) 20230304.7968 <143c (Yutaka Maeda) 20230305.8151 150c (Yutaka Maeda) 20230305.8151 150c (Yutaka Maeda)

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[vsnet-newvar 9856] CRTS J022411.4+355919 bright outburst
by Taichi Kato 06 Mar '23

06 Mar '23

CRTS J022411.4+355919 bright outburst May be a superoutburst. http://gsaweb.ast.cam.ac.uk/alerts/alert/Gaia23azi/ Gaia23azi AT2023ctt 2023-03-04 21:29:14 36.04769 35.98848 15.78 18.86 0.67 unknown 2023-03-06 08:23:39

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[vsnet-newvar 9855] MAXI J1834-021 (ATel 15932)
by Taichi Kato 06 Mar '23

06 Mar '23

MAXI J1834-021 (ATel 15932) ATEL #15932 ATEL #15932 Title: MAXI J1834-021: Swift/XRT detection and localization Author: J. A. Kennea (PSU), K. L. Page (Leicester) and H. Negoro (Nihon U) Queries: jak51(a)psu.edu Posted: 6 Mar 2023; 21:54 UT Subjects:X-ray, Transient MAXI reported a new X-ray transient, MAXI J1834-021 (ATEL #15929), first seen around February 5th, 2023. On March 6th, 2023 Swift performed a target of opportunity observation, consisting of 7 pointings of 300s each with XRT in Photon Counting mode, in order to cover the MAXI error region. We find a single bright, uncatalogued point source inside the MAXI error region at the following coordinates: RA/Dec(J2000) = 279.0362, -2.2872, which is equivalent to: RA(J2000) =18h 36m 08.70s, Dec(J2000) = -02d 17m 13.9s, with an error radius 3.5 arc-seconds (90% confidence). This position does not much the position of any known X-ray transient, therefore we consider this the likely counterpart of MAXI J1834-021, and confirm that this is a new transient. The position is coincident with two stars in the Gaia EDR3 catalog, Gaia EDR3 4259671048608866560 and Gaia EDR3 4259671052930848384, with magnitudes G=15.84 and G=20.79 respectively. It$B!G(Bs not possible to rule out either counterpart based on the XRT position. The source is bright, with a pile-up corrected count rate of 4.4 +/- 0.6 count/s. The spectrum is well described by an absorbed power-law model, with N_H = 1.46 x 10^22 cm^-2, photon index = 2.2 +/- 1.0 and an observed flux of 2.2 +/- 0.9 x 10^-10 erg/s/cm^2 (0.3-10 keV). We encourage follow-up to identify this new transient.

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