- vsnet-alert - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-alert 26951] EF Peg outburst
by Hiroyuki Maehara 30 Sep '22

30 Sep '22

Visual magnitude estimates by VSOLJ members object YYYYMMDD(UT) mag code PEGEF 20220930.622 133 Mhh.VSOLJ PEGEF 20220930.654 130 Mhh.VSOLJ Observer: Hiroyuki Maehara (Okayama, Japan) Instruments: 30cmL

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[vsnet-alert 26949] MASTER OT J001204.00-412337.4: sixth rebrightening
by Taichi Kato 29 Sep '22

29 Sep '22

MASTER OT J001204.00-412337.4: sixth rebrightening Josch Hambsch detected another rebrightening on Sep. 29 (15.9 mag).

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[vsnet-alert 26865] TCP J22561804+4109534: new WZ Sge-type dwarf nova
by tonny.vanmunster＠gmail.com 29 Sep '22

29 Sep '22

Dear colleagues, I have just finished analysing my unfiltered CCD observations of TCP J22561804+4109534, obtained on 2022, July 04/05 at CBA Belgium Observatory, using a 0.40-m f/10.0 telescope and QHY-286M CMOS camera under clear skies. I have been observing this object during multiple nights between June 27th and now. On all previous nights, no obvious modulations were visible in the light curve, except for last night when superhumps with an amplitude of 0.14 mag became very clearly visible. A period analysis using the ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.0), yields a combined superhump period of 0.0650 +/- 0.0011d. The object was at mag CV = 15.3 on Jul 05th. The superhump profile shows no signs of a double-waved pattern, and I could not detect early superhumps in my data. Yet, the large outburst amplitude of ~7.4 mag, and the long time for superhumps to develop (approx. 9 days) make this a very likely WZ Sge-type dwarf nova. Follow-up observations are recommended to further track the evolution of the superhumps. I will send my observations to AAVSO, CBA and VSNET for further analysis. Best regards Tonny --- Tonny Vanmunster CBA Belgium Observatory CBA Extremadura Observatory http://www.cbabelgium.com PERANSO : The Light Curve and Period Analysis Software http://www.peranso.com ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/

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[vsnet-alert 26947] ASASSN-19abr outburst
by Taichi Kato 29 Sep '22

29 Sep '22

ASASSN-19abr outburst YYYYMMDD(UT) mag observer 20220914.5495 <154c (Yutaka Maeda) 20220915.5800 <158c (Yutaka Maeda) 20220919.5428 <154c (Yutaka Maeda) 20220920.5683 <160c (Yutaka Maeda) 20220927.512 153C (Mitsutaka Hiraga)

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[vsnet-alert 26946] MASTER OT J053628.39+135341.7: likely superoutburst
by Taichi Kato 29 Sep '22

29 Sep '22

MASTER OT J053628.39+135341.7: likely superoutburst Type from ZTF data. The 2020 Jan. superoutburst had a precursor. YYYYMMDD(UT) mag observer 20220919.4041 16.617zg (ZTF Alert DC mag (Masci+ 2019)) 20220919.4874 16.572zg (ZTF Alert DC mag (Masci+ 2019)) 20220921.4699 16.499zg (ZTF Alert DC mag (Masci+ 2019)) 20220924.4648 16.752zr (ZTF Alert DC mag (Masci+ 2019)) 20220924.5015 16.864zg (ZTF Alert DC mag (Masci+ 2019)) 20220926.4459 17.232zg (ZTF Alert DC mag (Masci+ 2019))

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[vsnet-alert 26945] ASASSN-16cz likely superoutburst
by Taichi Kato 28 Sep '22

28 Sep '22

ASASSN-16cz likely superoutburst Type from ZTF data. The 2020 Oct. superoutburst was followed by a rebrightening.

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[vsnet-alert 26944] RY Sgr fading rapidly
by Taichi Kato 28 Sep '22

28 Sep '22

RY Sgr fading rapidly YYYYMMDD(UT) mag observer 20220814.512 71 (Masashi Nakatani) 20220818.510 71 (Noriaki Onodera) 20220818.510 75 (Masashi Nakatani) 20220819.508 72 (Noriaki Onodera) 20220821.528 73 (Noriaki Onodera) 20220827.6028 8.05V (Masayuki Moriyama) 20220828.500 77 (Noriaki Onodera) 20220830.137 8.01TG (Gary Poyner) 20220831.194 7.78TG (Gary Poyner) 20220831.8785 79 (Jose Ripero) 20220903.201 7.64TG (Gary Poyner) 20220903.8750 74 (Jose Ripero) 20220908.425 72 (Hiroyuki Maehara) 20220912.460 74 (Noriaki Onodera) 20220912.499 72 (Hiroyuki Maehara) 20220916.514 77 (Noriaki Onodera) 20220917.467 78 (Noriaki Onodera) 20220920.8646 84 (Jose Ripero) 20220921.460 80 (Noriaki Onodera) 20220926.451 94 (Noriaki Onodera) 20220926.8646 97 (Jose Ripero)

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[vsnet-alert 26943] V482 Cyg rising
by Taichi Kato 28 Sep '22

28 Sep '22

V482 Cyg rising So I must point again that Jose Ripero did not *know* that the object is already rising. The V-data suggest that the rise took place earlier than most visual observers noticed it. YYYYMMDD(UT) mag observer 20220829.058 13.98V (Gary Poyner) 20220829.9194 140 (Eddy Muyllaert) 20220829.962 139 (Gary Poyner) 20220830.971 138 (Gary Poyner) 20220831.5184 13.65V (Seiichiro Kiyota) 20220831.5189 12.65Rc (Seiichiro Kiyota) 20220831.5193 11.59Ic (Seiichiro Kiyota) 20220831.9097 <137 (Jose Ripero) 20220901.940 14.62 (Pavol A. Dubovsky) 20220901.9479 138 (Eddy Muyllaert) 20220903.8993 <137 (Jose Ripero) 20220903.985 14.83 (Pavol A. Dubovsky) 20220904.9243 140 (Eddy Muyllaert) 20220905.4110 12.87V (Minoru Sato) 20220905.9201 <137 (Jose Ripero) 20220907.023 136 (Gary Poyner) 20220907.700 133 (Hiroyuki Maehara) 20220908.983 131 (Gary Poyner) 20220910.016 12.92V (Gary Poyner) 20220910.017 12.52C (Gary Poyner) 20220910.017 12.97TG (Gary Poyner) 20220910.4133 12.78V (Minoru Sato) 20220910.8451 130 (Eddy Muyllaert) 20220910.949 129 (Gary Poyner) 20220914.3975 12.63V (Minoru Sato) 20220915.947 128 (Gary Poyner) 20220916.912 128 (Gary Poyner) 20220917.946 127 (Gary Poyner) 20220918.949 12.85 (Pavol A. Dubovsky) 20220919.8188 128 (Eddy Muyllaert) 20220920.9014 <137 (Jose Ripero) 20220921.923 126 (Gary Poyner) 20220922.065 12.51V (Gary Poyner) 20220923.919 124 (Gary Poyner) 20220924.4302 12.34V (Minoru Sato) 20220924.980 122 (Gary Poyner) 20220926.9014 <137 (Jose Ripero)

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[vsnet-alert 26942] Re: Fwd: GDS_J1830235-135539: a new symbiotic nova in Scutum:
by Kenta TAGUCHI 27 Sep '22

27 Sep '22

Dear Sebastián, Sorry for the late response. It seems the list didn't forward your e-mail for some reason (and I thank Keisuke for forwarding it to me). I apologize we confused you. "Identical" was my mistake and overstatement. Thank you very much for pointing it out. We pointed the telescope to the position of Gaia EDR3 4104372315454847232 (18:30:23.466, -13:55:42.17). I confirmed the object was almost at the center of the IFU (FoV 8.4'' x 8.0''), and therefore the star should prefer > 1) 18 30 23.47 -13 55 42.0 (2.7" away from the GDS position) 2MASS > J18302347-1355421 J= 8.28, H= 6.83, K= 5.87, G= 14.36, BP= 18.30, RP= > 12.72 Best Regards, Kenta On 2022/09/27 15:59, Keisuke Isogai wrote: > 転送シアmス > > > -------- Forwarded Message -------- > Subject: Re: [vsnet-alert 26940] GDS_J1830235-135539: a new symbiotic > nova in Scutum: > Date: Mon, 26 Sep 2022 13:12:14 -0300 > From: Sebastián Otero <sebastian(a)aavso.org> > To: vsnet-alert(a)ooruri.kusastro.kyoto-u.ac.jp, Keisuke Isogai > <isogai(a)kusastro.kyoto-u.ac.jp> > > > > The Pan-STARRS1 image shows nebulosity around the mira variable so > this supports the ID with the symbiotic nova. > Also, the other red star is 5" away from this one, so I assume that > one is not the star that now has a spectrum. > > The statement "The position is identical to that of a known variable > star GDS J1830235-135539" is what is still causing confusion. > Can you please comment? > > Cheers, > Sebastian > > > >> Hello all, >> >> This object really deserves discussion. >> There hasn't been any comment about its identification. Its GDS >> coordinates do not match the position of the actual mira variable. >> >> There are two very red objects 3" away from the GDS position (18 30 >> 23.57 -13 55 39.9) but the closest object in Gaia DR3(1.1" away) is >> none of them and is not a red star. >> >> 18 30 23.63 -13 55 39.2 Gaia DR3 4104372315454096896 - G= 15.29, BP= >> 15.80, RP= 14.43 >> >> Since the GDS variations show the mira-like activity, the catalogue >> entry should indeed be identified as the red variable, but the light >> curve and measured position and surely those of a blend. >> >> The same happens in the ATLAS catalogue, the variable entry is ATO >> J277.5984-13.9275 (LPV - 319/329 d., c= 15.32 - 15.63) at 18 30 >> 23.63 -13 55 39.3, which matches Gaia DR3 4104372315454096896's >> position but the period and type clearly indicates the variable is >> not that one. >> >> The two red objects in 2MASS are (with their Gaia DR3 J2000.0 positions): >> >> 1) 18 30 23.47 -13 55 42.0 (2.7" away from the GDS position) 2MASS >> J18302347-1355421 J= 8.28, H= 6.83, K= 5.87, G= 14.36, BP= 18.30, >> RP= 12.72 >> 2) 18 30 23.54 -13 55 36.9 (2.9" away from the GDS position) 2MASS >> J18302354-1355369 J= 12.06, H= 9.24, K= 8.14, G= 16.50, BP= 19.13, >> RP= 15.08 >> >> There is a third entry in 2MASS at 18 30 23.54 -13 55 37.8 (2MASS >> J18302353-1355377 J= 9.54, H= 8.14, K= 7.21) which is actually a >> blend of the other two (with the flag "photometric confusion") >> >> Star 1) is the actual variable star. It is Gaia DR3 >> 4104372315454847232 (LPV - 322.8 d. G= 12.6 - 14.8). >> It is also OGLE BLG-LPV-264465 (OGLE BLG575.27.48590), classified as >> M with a period of 315.3 d., mean Ic = 12.13 and amplitude 2.89 mag. >> >> So we know which is the mira variable. But is is the nova-like object? >> What about the other red one? >> And what about the bluer star? >> There are also two other stars in Gaia DR3 (without color >> information) which are part of the blend in GDS and ATLAS: >> >> 18 30 23.63 -13 55 41.3 (1.7" away from the GDS position) G= 19.80 >> 18 30 23.75 -13 55 39.3 (2.6" away from the GDS position) G= 17.94 >> >> I agree that a NC-type brightening and a mira variable look >> compatible (and make the identification with the bluer or closer >> objects less likely), but the presence of the other red object casts >> some doubts about the identification. >> I think accurate astrometry is needed here to properly identified the >> outbursting star. >> >> Cheers, >> Sebastian >> -- >> Sebastian Otero >> VSX Team >> American Association of Variable Star Observers >> >> “The mission of the AAVSO is to enable anyone, anywhere, >> to participate in scientific discovery through variable star astronomy” >> >> www.aavso.org >> >> >>> GDS_J1830235-135539: a new symbiotic nova in Scutum: >>> >>> coordinates: 18 30 23.57 -13 55 39.9 >>> >>> ATel #15623: Spectroscopic confirmation of recent brightening of GDS >>> J1830235-135539 as a symbiotic nova and ASASSN-22lk as a large-amplitude >>> dwarf nova >>> https://www.astronomerstelegram.org/?read=15623 >>> VSX:https://www.aavso.org/vsx/index.php?view=detail.top&oid=456166 >>> Light curve and spectrum: >>> www.kusastro.kyoto-u.ac.jp/~kentagch/atel/GDS_J1830235-135539.pdf >>> >>> Clear skies, >>> >>> Robert >> >> > > > -- > Sebastian Otero > VSX Team > American Association of Variable Star Observers > > “The mission of the AAVSO is to enable anyone, anywhere, > to participate in scientific discovery through variable star astronomy” > > www.aavso.org -- ________________________________________________________________ 田口健太　(TAGUCHI, Kenta) 京都大学大学院理学研究科宇宙物理学教室 (Department of Astronomy, Graduate School of Science, Kyoto University) kentagch(a)kusastro.kyoto-u.ac.jp 09090536980

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[vsnet-alert 26941] ASASSN-22lj: SU UMa star below the period minimum
by Taichi Kato 27 Sep '22

27 Sep '22

ASASSN-22lj: SU UMa star below the period minimum Josch Hambsch has reported observations. Although nightly coverage was short, the object clearly shows superhumps with an amplitude of 0.09 mag. The period (with aliases) is 0.03761(2) d, indicating that the object is likely an EI Psc star. Observations from different longitudes are desired.

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