AT 2021nwa
RA/DEC (2000)
15:53:51.279 +55:35:19.67
238.46366275909 +55.58879755
Type
TDE
Redshift
0.047
Related AstroNotes: 2021-309
Reporting Group
ZTF
Discovering Data Source
ZTF
Discovery Date
2021-05-11 09:17:54.816
TNS AT
Y
Public
Y
Discovery Mag
20.5804
Filter
g-ZTF
Reporter/s
K. De (Caltech) on behalf of ZTF

Spectra

 AT_2021nwa - 2021-07-06 06:25:18 Keck1 / LRIS (ZTF)z=
 AT_2021nwa - 2021-06-17 04:53:56 P60 / SEDM (ZTF)z=
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   Binning factor: (rounded to nearest integer >1)
Mouse hovers at WL: 0 (rest),0 (observed)
Spectra
SelectIDObs-date (UT)Tel / InstExp-TimeObserver/sReducer/sGroupSpectrum ascii fileSpectrum fits fileSpec. TypeAssoc. GroupsEnd prop. periodRemarks
154952021-07-06 06:25:18Keck1 / LRIS300Yuhan Yao, Yashvi SharmaZTF tns_2021nwa_2459401.767569_Keck1_LRIS_ZTF.datObjectZTF
99412021-06-17 04:53:56P60 / SEDM2700ZTF-SEDM teamZTF tns_2021nwa_2459382.7041167_P60_SEDM_ZTF.txtObjectZTF
Light Curves
FilterTel / InstObs-date rangePhotometry
orange-ATLASATLAS-HKO_ATLAS-022021-06-07 11:44:10 - 2021-06-07 11:44:101
Photometry
IDObs-dateMag. / FluxErrLim. Mag./FluxUnitsFilterTel / InstExp-timeObserver/sRemarks
2204222021-06-07 11:44:1019.52ABMagorange-ATLASATLAS-HKO_ATLAS-0230Robot[Last non detection]
cyan-ATLASATLAS-MLO_ATLAS-012021-06-09 10:03:22 - 2021-06-09 10:03:221
Photometry
IDObs-dateMag. / FluxErrLim. Mag./FluxUnitsFilterTel / InstExp-timeObserver/sRemarks
2204232021-06-09 10:03:2219.4030.12120.03ABMagcyan-ATLASATLAS-MLO_ATLAS-0130Robot
g-ZTFP48_ZTF-Cam2021-05-11 09:17:55 - 2021-06-17 07:25:352
Photometry
IDObs-dateMag. / FluxErrLim. Mag./FluxUnitsFilterTel / InstExp-timeObserver/sRemarks
2256192021-06-17 07:25:3518.840.1120.37ABMagg-ZTFP48_ZTF-Cam30
2166672021-05-11 09:17:5520.580420.7522ABMagg-ZTFP48_ZTF-Cam30None
r-ZTFP48_ZTF-Cam2021-05-11 07:53:23 - 2021-06-17 08:18:393
Photometry
IDObs-dateMag. / FluxErrLim. Mag./FluxUnitsFilterTel / InstExp-timeObserver/sRemarks
2256202021-06-17 08:18:3919.30.1420.24ABMagr-ZTFP48_ZTF-Cam30
2256182021-06-15 08:20:3720.0347ABMagr-ZTFP48_ZTF-Cam30[Last non detection]
2166662021-05-11 07:53:2320.7316ABMagr-ZTFP48_ZTF-Cam30None[Last non detection]
AT Reports
IDTime received (UT)SenderReporter/sReportting groupDisc. Data SourceRADECDiscovery date (UT)Discovery Mag.FilterRelated filesAT TypeInternal nameAssoc. GroupsEnd prop. periodRemarks
1160042021-07-04 06:09:25ZTF_AMPEL_COMPLETEJ. Nordin, V. Brinnel, J. van Santen (HU Berlin), A. Gal-Yam, O. Yaron, S. Schulze (Weizmann) on behalf of ZTFAMPELZTF15:53:51.279+55:35:19.672021-06-17 07:25:34.75218.84g-ZTFPSNZTF21abcgnqnZTFNED z 0.047.
1130802021-06-11 13:15:50ATLAS_Bot1J. Tonry, L. Denneau, A. Heinze, H. Weiland (IfA, University of Hawaii), B. Stalder (LSST), A. Rest (STScI), C. Stubbs (Harvard University), K. W. Smith, S. J. Smartt, D. R. Young, S. Srivastav, O. McBrien, M. Fulton, J. Gillanders, C. Webb (Queen's University Belfast), T.-W. Chen (MPE), D. E. Wright (University of Minnesota), J. Anderson (ESO)ATLASATLAS15:53:51.270+55:35:19.752021-06-09 10:03:21.60019.403cyan-ATLASPSNATLAS21sjlATLAS
1113522021-05-29 23:00:32ZTF_CLU_PUBLICK. De (Caltech) on behalf of ZTFZTFZTF15:53:51.280+55:35:19.742021-05-11 09:17:54.81620.5804g-ZTFPSNZTF21abcgnqnZTF
Classification Reports
IDTime received (UT)SenderClassifier/sGroupClassificationRedshiftRelated filesAssoc. GroupsEnd prop. periodRemarksADS Bibcode
154132023-08-17 19:34:12yyaoYuhan YaoZTFTDE0.047ZTFUpload a spectrum published in Yao et al. 2023 ApJL in press (arxiv: 2303.06523).2023TNSCR2004....1Y
99242021-06-21 21:21:57yyaoYuhan Yao (Caltech), Suvi Gezari (STScI), Sjoert van Velzen (Leiden University), Erica Hammerstein (UMD), Jean Somalwar (Caltech)ZTFTDE0.047ZTFWe report the classification of the optical transient ZTF21abcgnqn/AT2021nwa (RA=15:53:51.28, Dec=+55:35:19.82) as a tidal disruption event (TDE). AT2021nwa was first detected by the Zwicky Transient Facility (ZTF) on 2021 May 11 at a magnitude of g = 20.58 +- 0.27 mag. Its host galaxy was observed by the SDSS spectroscopy survey on 2001 May 27, indicating an early-type quiescent galaxy at a redshift of z=0.047. AT2021nwa was identified as a TDE candidate due to its long rise time (>40 days) and blue color (g-r ~ -0.3 mag). We obtained a low-resolution (R~100) spectrum with the Spectral Energy Distribution Machine (SEDM, Blagorodnova et al. 2018; Rigault et al. 2019) on 2021 June 17. Compared with the historical SDSS spectrum, the SEDM spectrum shows a much bluer continuum, and a broad emission feature around He II 4686 A. This is reminiscent of the TDE-He spectral type (van Velzen et al. 2021).2021TNSCR2155....1Y

Comments

Object coordinates updated according to AT-report 116004 of Group ZTF
Previous RA, DEC: 15:53:51.280, +55:35:19.74 (238.463665, +55.5888157)
Updated RA, DEC: 15:53:51.279, +55:35:19.67 (238.46366275909, 55.58879755)