2025efc | Transient Name Server

RA/DEC (2000)

09:34:43.545 -21:55:51.98

143.6814375 -21.9311055

Type

SN Ia

Redshift

0.0163

Discovery Report Classification Report

Related AstroNotes: 2025-87

Reporting Group

ATLAS

Discovering Data Source

ATLAS

Discovery Date

2025-03-12 03:39:50.688

TNS AT

Public

Discovery Mag

17.445

Filter

orange-ATLAS

Reporter/s

J. Tonry, L. Denneau, H. Weiland, R. Siverd (IfA, University of Hawaii), N. Erasmus, W. Koorts (South African Astronomical Observatory), A. Jordan, V. Suc (UAI, Obstech), S. J. Smartt, K. W. Smith (Oxford/QUB), D. R. Young, M. Nicholl, M. Fulton, M. McCollum, T. Moore, J. Weston, X. Sheng, C. R. Angus, A. Wilson, A. Aamer, D. Magill (QUB), P. Ramsden (Birmingham/QUB), L. Shingles (GSI/QUB), S. Srivastav, J. H. Gillanders, H. Stevance, A. J. Cooper, F. Stoppa, J. Tweddle (Oxford), L. Rhodes (TSI/McGill), A. Rest (STScI), T.-W. Chen (NCU), C. Stubbs (Harvard), J. S. Sommer (LMU), B. P. Schmidt (ANU)

NED SIMBAD DECaLS PanSTARRS-1 SkyMapper VizieR WISE DSS ADS

Light curves

▌

ATLAS-CHL_ATLAS-04_orange

▌

P48_ZTF-Cam_r

Pointer position (MJD, Mag, Abs.Mag): (0.00, 0.00, 0.00)

Spectra

Select	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
	20569	2025-03-13 10:17:27	FTN / FLOYDS-N	2700	LCO	Moira Andrews	None	tns_2025efc_2025-03-13_10-17-27_FTN_FLOYDS-N_None.txt		Object
Binning factor: (rounded to nearest integer >1) Mouse hovers at WL: 0 (rest), 0 (observed) ▌Show H at z=v_exp= km/s ▌Show He at z=v_exp= km/s ▌Show He II at z=v_exp= km/s ▌Show C II at z=v_exp= km/s ▌Show C III at z=v_exp= km/s ▌Show C IV at z=v_exp= km/s ▌Show N II at z=v_exp= km/s ▌Show N III at z=v_exp= km/s ▌Show N IV at z=v_exp= km/s ▌Show N V at z=v_exp= km/s ▌Show O at z=v_exp= km/s ▌Show [O I] at z=v_exp= km/s ▌Show O II at z=v_exp= km/s ▌Show [O II] at z=v_exp= km/s ▌Show [O III] at z=v_exp= km/s ▌Show O V at z=v_exp= km/s ▌Show O VI at z=v_exp= km/s ▌Show Na at z=v_exp= km/s ▌Show Mg at z=v_exp= km/s ▌Show Mg II at z=v_exp= km/s ▌Show Si II at z=v_exp= km/s ▌Show S II at z=v_exp= km/s ▌Show Ca II at z=v_exp= km/s ▌Show [Ca II] at z=v_exp= km/s ▌Show Fe II at z=v_exp= km/s ▌Show Fe III at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Tellurics ▌Show Galaxy lines at z= ▌Show WR-WN at z=v_exp= km/s ▌Show WR-WC/O at z=v_exp= km/s Remarks

Light Curves

Filter

Tel / Inst

Obs-date range

JD Range

Photometry

orange-ATLAS

ATLAS-CHL_ATLAS-04

2025-03-11 04:13:53 - 2025-03-12 03:39:51

2460745.67631 - 2460746.65267

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
475135	2025-03-12 03:39:51	2460746.65267	17.445	0.12	18.02	ABMag	orange-ATLAS	ATLAS-CHL_ATLAS-04	30	Robot
475134	2025-03-11 04:13:53	2460745.67631			18.58	ABMag	orange-ATLAS	ATLAS-CHL_ATLAS-04	30	Robot	[Last non detection]

r-ZTF

P48_ZTF-Cam

2025-03-09 07:35:09 - 2025-03-16 06:04:36

2460743.8160764 - 2460750.7531944

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
476447	2025-03-16 06:04:36	2460750.7531944	16.0059	0.0330294	19.442	ABMag	r-ZTF	P48_ZTF-Cam	30	Robot	Data provided by ZTF
476446	2025-03-09 07:35:09	2460743.8160764			19.2899	ABMag	r-ZTF	P48_ZTF-Cam	30	Robot	[Last non detection] Data provided by ZTF

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	Bibcode	Unreal	Auto classification
248641	2025-03-16 22:17:06	ALeRCE	F. Forster,F.E. Bauer,G. Pignata et al.	ALeRCE	ZTF	09:34:43.545	-21:55:51.98	2025-03-16 06:04:35.996	16.0059	r-ZTF		PSN	ESO 565-19	ZTF25aaiwalj	ZTF		Early SN candidate (r-rise > 0.47+-0.00 mag/day) classified using ALeRCE's stamp classifier (Carrasco-Davis et al. 2021) and the public ZTF stream. Discovery image and light curve in http://alerce.online/object/ZTF25aaiwalj		N
247802	2025-03-12 16:02:30	ATLAS_Bot1	J. Tonry,L. Denneau,H. Weiland et al.	ATLAS	ATLAS	09:34:43.525	-21:55:52.06	2025-03-12 03:39:50.688	17.445	orange-ATLAS		PSN		ATLAS25cqk	ATLAS			2025TNSTR.963....1T	N

Classification Reports

Time received (UT)

Sender

Classifier/s

Group

Classification

Redshift

Spectra

Related files

Assoc. Groups

End prop. period

Remarks

ADS Bibcode

20569

2025-03-13 22:31:29

Moira Andrews

Moira Andrews (UCSB/LCO), Joseph Farah (UCSB/LCO), D. Andrew Howell (UCSB/LCO), Curtis McCully (UCSB/LCO)

None

SN Ia

0.0163

We report the classification of SN 2025efc as SN Ia. The spectrum shows a best match to Ia norm SN 2003W from SNID (Blondin & Tonry 2007, ApJ, 666, 1024) 11 days before peak. The object redshift is acquired from the nearby host of ESO 565- G 019 (z=0.016285, value from NED). Additional follow-up is encouraged.

2025TNSCR.977....1A

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
20569	2025-03-13 10:17:27	FTN / FLOYDS-N	2700	LCO	Moira Andrews	None	tns_2025efc_2025-03-13_10-17-27_FTN_FLOYDS-N_None.txt		Object

Comments

Object coordinates updated

Object coordinates updated according to AT-report 248641 of Group ZTF
Previous RA, DEC: 09:34:43.525, -21:55:52.06 (143.681355, -21.9311266667)
Updated RA, DEC: 09:34:43.545, -21:55:51.98 (143.6814375, -21.931105499999997)