RA/DEC (2000)
04:53:00.325 -11:01:40.36
73.251354 -11.027879
Type
SN Ib-pec
Redshift
0.03
Discovery ReportClassification Report
Related AstroNotes: 2025-269
Reporting Group
GOTO
Discovering Data Source
GOTO
Discovery Date
2025-08-17 18:02:44.160
TNS AT
Y
Public
Y
Discovery Mag
16.72
Filter
L-GOTO
Reporter/s
D. O'Neill, K. Ackley, M. Dyer, J. Lyman, K. Ulaczyk, D. Steeghs, D. Galloway, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. Breton, J. Casares, L. Nuttall, B. Godson, T. Killestein, A. Kumar, M. Pursiainen, on behalf of GOTO collaboration
NEDSIMBADDECaLSPanSTARRS-1SkyMapperVizieRWISEDSSADS

Spectra

 ▌SN_2025ugl - 2025-08-27 05:42:19 NOT / ALFOSC (GOTO)z=
 ▌SN_2025ugl - 2025-08-22 05:36:23 LT / SPRAT (GOTO)z=
▌Show H at z=vexp= km/s
▌Show He at z=vexp= km/s
▌Show He II at z=vexp= km/s
▌Show C II at z=vexp= km/s
▌Show C III at z=vexp= km/s
▌Show C IV at z=vexp= km/s
▌Show N II at z=vexp= km/s
▌Show N III at z=vexp= km/s
▌Show N IV at z=vexp= km/s
▌Show N V at z=vexp= km/s
▌Show O at z=vexp= km/s
▌Show [O I] at z=vexp= km/s
▌Show O II at z=vexp= km/s
▌Show [O II] at z=vexp= km/s
▌Show [O III] at z=vexp= km/s
▌Show O V at z=vexp= km/s
▌Show O VI at z=vexp= km/s
▌Show Na at z=vexp= km/s
▌Show Mg at z=vexp= km/s
▌Show Mg II at z=vexp= km/s
▌Show Si II at z=vexp= km/s
▌Show S II at z=vexp= km/s
▌Show Ca II at z=vexp= km/s
▌Show [Ca II] at z=vexp= km/s
▌Show Fe II at z=vexp= km/s
▌Show Fe III at z=vexp= km/s
▌Show Å at z=vexp= km/s
▌Show Å at z=vexp= km/s
▌Show Å at z=vexp= km/s
▌Show Å at z=vexp= km/s
▌Show Tellurics 
▌Show Galaxy lines at z=
▌Show WR-WN at z=vexp= km/s
▌Show WR-WC/O at z=vexp= km/s
   Binning factor: (rounded to nearest integer >1)
Mouse hovers at WL: 0 (rest),0 (observed)

Light curves

 ▌GOTO-S_GOTO-4_L
 ▌GOTO-S_GOTO-3_L
   
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
21882 2025-08-27 05:42:19 NOT / ALFOSC M. Pursiainen, I. Worssam M. Pursiainen, I. Worssam GOTO tns_2025ugl_2025-08-27_05-42-19_NOT_ALFOSC_GOTO.dat Object
21845 2025-08-22 05:36:23 LT / SPRAT Robotic GOTO tns_2025ugl_2025-08-22_05-36-23.472_LT_SPRAT_GOTO.dat Object
Light Curves
Filter Tel / Inst Obs-date range JD Range Photometry
L-GOTO GOTO-S_GOTO-4 2025-08-17 18:02:44 - 2025-08-17 18:02:44 2460905.251903 - 2460905.251903 1
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
509776 2025-08-17 18:02:44 2460905.251903 16.72 0.02 ABMag L-GOTO GOTO-S_GOTO-4 180
L-GOTO GOTO-S_GOTO-3 2025-08-12 19:12:42 - 2025-08-12 19:12:42 2460900.300489 - 2460900.300489 1
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
509775 2025-08-12 19:12:42 2460900.300489 18.7 ABMag L-GOTO GOTO-S_GOTO-3 180 [Last non detection]
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
266295 2025-08-17 18:28:06 GOTO_bot D. O'Neill,K. Ackley,M. Dyer et al. GOTO GOTO 04:53:00.325 -11:01:40.36 2025-08-17 18:02:44.160 16.72 L-GOTO Other GOTO25fxv GOTO 2025TNSTR3243....1O N
Classification Reports
ID Time received (UT) Sender Classifier/s Group Classification Redshift Spectra Related files Assoc. Groups End prop. period Remarks ADS Bibcode
21882 2025-08-27 11:50:10 David O'Neill M. Pursiainen, I. Worssam, D. O'Neill, J. Lyman, T. Killestein, K. Ackley, M. Dyer, K. Ulaczyk, D. Steeghs, D. Galloway, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. Breton, J. Casares, L. Nuttall, B. Godson, A. Kumar on behalf of GOTO collaboration GOTO SN Ib-pec 0.03 1 GOTO Spectrum was matched to type Ib SNe using SNID-SAGE. Spectrum is similar to SN 2009er and shows broad P-cygni-like features that appear to be consistent with He at z~0.025. However we note that there is large scatter in the inferred redshifts and ages of the SN from template matching, with most over-estimating the age. The object is bright (M <-18) and is declining at a rate of >1 mag/week. Therefore we classify as a Ib-pec We find that the photometric redshift of the nearby galaxy from legacy survey DR10 is z=0.035±0.018, consistent with the result from template matching. 2025TNSCR3404....1P
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
21882 2025-08-27 05:42:19 NOT / ALFOSC M. Pursiainen, I. Worssam M. Pursiainen, I. Worssam GOTO tns_2025ugl_2025-08-27_05-42-19_NOT_ALFOSC_GOTO.dat Object
21845 2025-08-22 12:49:56 Miika Pursiainen M. Pursiainen, D. O'Neill, J. Lyman, P. Charalampopoulos, G. Ramsay, B. Warwick, K. Ackley, M. Dyer, F. Jiménez-Ibarra, K. Ulaczyk, D. Steeghs, D. Galloway, V. Dhillon, P. O'Brien, K. Noysena, R. Kotak, R. Breton, L. Nuttall, E. Pallé, D. Pollacco, T. Killestein, A. Kumar on behalf of GOTO collaboration GOTO SN 1 3 GOTO Spectrum shows blue continuum with shallow, broad P-Cygni lines. Due to the relatively low SNR of the spectrum, the classification is not immediately obvious even if SN-nature is likely due to the off-nuclear host association with extended, blue galaxy at an unknown redshift. We find reasonable template matches with e.g. pre-peak Type IIb SNe (z~0.14), SLSN 2015bn near-peak (z~0.17) and SLSN-I PTF10aagc (z~0.035), and the breadth of the matched SN types and redshifts underlines the difficulties in determining the exact type. Further follow-up is encouraged. 2025TNSCR3326....1P
Related files
File Comments Last Modified (UT) Modified By
tns_2025ugl_atrep_21845_GOTO.png 2025-08-22 12:49:56 Miika Pursiainen
tns_2025ugl_atrep_21845_GOTO_0.png 2025-08-22 12:49:56 Miika Pursiainen
tns_2025ugl_atrep_21845_GOTO_1.png 2025-08-22 12:49:56 Miika Pursiainen
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
21845 2025-08-22 05:36:23 LT / SPRAT Robotic GOTO tns_2025ugl_2025-08-22_05-36-23.472_LT_SPRAT_GOTO.dat Object

Comments