RA/DEC (2000)
03:17:36.460 +74:59:31.80
49.401917 +74.992167
Type
CV
Redshift
0
Reporting Group
XOSS
Discovering Data Source
XOSS
Discovery Date
2025-09-21 18:55:54.048
TNS AT
Y
Public
Y
Discovery Mag
13.78
Filter
Clear-
Reporter/s
Ziyang Mai, Jianlin Xu, Mi Zhang, Guoyou Sun, Jiangao Ruan, Jingyuan Zhao, Wenjie Zhou, Yong Ma, Ye, Zhuoyang Chen (Xingming Obs.), Hanjie Tan (AUUK), Guangwei Wu (NAAA), Xing Gao, Ali Esamdin, Chunhai Bai, Yong Wang (XAO), on behalf of the KATS team

Spectra

 AT_2025ygf - 2025-09-22 21:12:08 Other / Other (XOSS)z=
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Light curves

 Other_Other_Clear
   
Pointer position (MJD, Mag, Abs.Mag): (0.00, 0.00, 0.00)
Spectra
ID Obs-date (UT) Tel / Inst Exp-Time Observer/s Reducer/s Group Spectrum ascii file Spectrum fits file Spec. Type Assoc. Groups End prop. period Remarks
22078 2025-09-22 21:12:08 Other / Other 12600 Xing Gao (Xingming Obs.) Jingyuan Zhao (Xingming Obs.) XOSS tns_2025ygf_2025-09-22_21-12-08_Other_Other_XOSS.DAT tns_2025ygf_2025-09-22_21-12-08_Other_Other_XOSS.fit Object We obtained a spectrum of the transient using the Alpy 600 spectrograph mounted on the 0.6-m f/8 Ritchey-Chretien telescope at Xingming Observatory.
Light Curves
Filter Tel / Inst Obs-date range JD Range Photometry
Clear- Other_Other 2025-09-21 18:55:54 - 2025-09-21 18:55:54 2460940.28882 - 2460940.28882 1
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
519128 2025-09-21 18:55:54 2460940.28882 13.78 20 VegaMag Clear- Other_Other 60 Xing Gao
AT Reports
ID Time received (UT) Sender Reporter/s Reporting group Disc. Data Source RA DEC Discovery date (UT) Discovery Mag. Filter Related files AT Type Host name Internal name Assoc. Groups End prop. period Remarks ADS Bibcode Unreal Auto classification
270928 2025-09-21 23:33:00 XOSS_Bot0 Ziyang Mai,Jianlin Xu,Mi Zhang et al. XOSS XOSS 03:17:36.460 +74:59:31.80 2025-09-21 18:55:54.048 13.78 Clear- Other KATS25S004 XOSS Cataclysmic variable candidate classified by XOSS. Details can be found at http://xjltp.china-vo.org/kats25s004.html 2025TNSTR3796....1M N
Classification Reports
ID Time received (UT) Sender Classifier/s Group Classification Redshift Spectra Related files Assoc. Groups End prop. period Remarks ADS Bibcode
22078 2025-09-23 11:52:15 Jingyuan Zhao Jingyuan Zhao, Xing Gao (Xingming Obs.) XOSS CV 0 1 XOSS Our spectrum shows a blue continuum with a series of prominent Balmer absorption lines. The spectral characteristics suggest AT 2025ygf is a dwarf nova. 2025TNSCR3833....1Z
Spectra
ID Obs-date (UT) Tel / Inst Exp-Time Observer/s Reducer/s Group Spectrum ascii file Spectrum fits file Spec. Type Assoc. Groups End prop. period Remarks
22078 2025-09-22 21:12:08 Other / Other 12600 Xing Gao (Xingming Obs.) Jingyuan Zhao (Xingming Obs.) XOSS tns_2025ygf_2025-09-22_21-12-08_Other_Other_XOSS.DAT tns_2025ygf_2025-09-22_21-12-08_Other_Other_XOSS.fit Object We obtained a spectrum of the transient using the Alpy 600 spectrograph mounted on the 0.6-m f/8 Ritchey-Chretien telescope at Xingming Observatory.

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