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GCN Circular 18824

Subject
LIGO/Virgo G211117: Summary of Pan-STARRS transients
Date
2016-01-04T17:12:47Z (8 years ago)
From
S. J. Smartt at Queens U Belfast <s.smartt@qub.ac.uk>
S. Smartt ((Queen���s University Belfast), K. C. Chambers, (IfA, University of Hawaii),
T.-W. Chen (MPE),K. Smith, D. Wright (QUB) , M. E. Huber, A. S. B. Schultz (IfA),
M. Coughlin (Harvard), L. Denneau, H. Flewelling, A. Heinze, R. Kotak (QUB),
E. A. Magnier, N. Primak, A. Rest (STScI),  A. Sherstyuk (IfA), B. Stalder (IfA),
C. W. Stubbs (Harvard), J. Tonry, C. Waters (IfA),  D. Young (QUB)

Further to Smith et al. (GCN 18811), Chambers et al. (18786), Frohmaier et al. (18806)
we report three further spectra from Gemini and a full summary of targets from all
spectra, cross-matching and Pan-STARRS data now available. Targets are
summarised as likely extragalactic transients, stellar variables, and AGN/QSO variables below. 

Three targets were observed with Gemini GMOS (GN-2015B-Q-4, PI. K. Chambers), 
with the R400 grating (4900-8000Angs) on 2016-01-01
PS15don is a type Ia,  z=0.16, at peak,
PS15doy is a type Ia,  z=0.19, probably 1991T-like at one weak post peak
PS15dpe is a type Ia, z=0.057 at about 10 days after peak. 
Hence all of these exploded well before G211117, and as apparently normal Ia SNe 
are unrelated. 

The only unusual target to date is PS15dpn (see Chambers et al. GCN 18811). 

Summary table of extragalactic transients (30) :
Name        RA (J2000)   Dec (J2000)  Disc. Date   Disc. MJD  Disc Mag
PS15dcq     03 22 55.83  +34 59 23.6  20151228.29  57384.29    19.99 (1) iPTF15fgy, SN Ia
PS15dov     03 43 57.36  +39 17 43.7  20151228.32  57384.32    19.73 SN II, GMOS
PS15dot     02 11 55.69  +13 28 17.8  20151228.34  57384.34    20.97 SN II,  GMOS
PS15coh     02 15 58.45  +12 14 13.6  20151228.34  57384.34    17.72 (2) ASASSN-15rw (SN Ia)
PS15dow     02 19 42.20  +14 09 54.7  20151228.34  57384.34    20.22 SN Ib, GMOS
PS15csf     02 26 02.24  +17 03 40.4  20151228.35  57384.35    18.68 (2) MASTER OT J022037.36+170217.5, LSQ15bwe (old)
PS15dom     02 34 45.62  +18 20 37.7  20151228.35  57384.35    19.01 (2) PSNJ02344555+1820390, iPTF15fdv (old)
PS15don     02 37 11.44  +19 03 20.2  20151228.35  57384.35    20.47 SN Ia, GMOS
PS15dox     02 40 15.05  +22 32 12.1  20151228.38  57384.38    19.23 SN Ia, PESSTO
PS15doy     02 47 54.16  +21 46 24.0  20151228.38  57384.38    20.75 SN Ia, GMOS
PS15dpq     03 09 12.74  +27 31 16.9  20151228.39  57384.39    18.84 SN Ia, PESSTO (iPTF15fel)
PS15dpa     02 57 56.02  +28 53 37.1  20151228.40  57384.40    19.51 SN Ia, PESSTO
PS15dpe     05 44 42.66  +52 24 57.9  20151228.43  57384.43    19.44 SN Ia, GMOS
PS15dpl     05 47 45.39  +53 36 32.4  20151228.43  57384.43    19.34 SN Ia GMOS
PS15dpn     02 32 59.75  +18 38 07.0  20151229.23  57385.23    20.69 see GCN 18811
PS15dpf     02 49 32.57  +21 47 09.4  20151229.24  57385.24    20.69
PS15doz     02 53 41.68  +27 29 57.8  20151229.25  57385.25    20.69
PS15dpc     03 55 46.16  +38 52 49.6  20151229.27  57385.27    20.95 SN II, GMOS
PS15dqc     05 51 13.43  +52 28 18.7  20151229.29  57385.29    21.16
PS15cvo     02 20 37.39  +17 02 17.9  20151229.31  57385.31    20.45 (2) MASTER and PSST detections in Nov 2015
PS15dpz     02 40 33.01  +23 00 10.8  20151229.32  57385.32    21.15
PS15dpb     03 42 23.40  +39 14 40.4  20151229.36  57385.36    20.20 SN II, GMOS
PS15dou     06 03 38.73  +54 41 12.1  20151229.56  57385.56    20.20
PS15dpx     06 04 35.54  +53 35 25.8  20151229.56  57385.56    20.76
PS15dpt     02 07 34.96  +11 03 25.2  20151230.22  57386.22    20.64
PS15dpy     02 28 22.75  +13 59 19.3  20151230.22  57386.22    21.31
PS15dpu     02 40 41.35  +16 49 52.0  20151230.22  57386.22    17.26 ASASSN-15un (3), spectrum scheduled on LT
PS15dqa     02 59 41.20  +25 14 12.2  20151230.24  57386.24    20.93 in NGC1156 at 7Mpc (GCN18811)
PS15dqe     06 05 26.88  +54 09 11.3  20151230.37  57386.37    21.51
PS16bp      03 05 29.46  +24 46 05.0  20160102.39  57389.39    17.45 spectrum scheduled on LT

Notes 
(1) Old SN from PSST (GCN. 18811) Observed by Copperwheat et al. (GCN18807), type Ia at 16d after peak.
(2) Old SNe known before G211118
(3) ASASSN-15un : discovered on 2015-12-28.22 by Masi et al. (ATel 8470)
not yet classified. In Mrk 1182, d=119 Mpc. Spectrum now scheduled on LT.

On closer inspection of multi-epoch Pan-STARRS data and the reference images,
we find that the following previously reported transients from Smith et al. (GCN18786)
are most likely not extragalactic transients :  one is a slow mover (not a recorded minor planet)
and 12 are most likely faint stellar variables (including 2 already report as stellar in GCN 18786)

Slow mover :
PS15dpr     03 16 12.16  +31 04 01.3  20151229.46  57385.46    19.78

Likely stellar variables : these objects either are close to the Galactic plane
(l,b coordinates given below), and/or do not have detections spanning multiple
nights.
Name        RA (J2000)   Dec (J2000)  Disc. Date   Disc. MJD  Disc Mag   l   b
PS15dpm     06 19 54.15  +54 18 10.3  20151229.56  57385.56    20.48  160.2 17.4
PS15dpv     03 40 02.91  +36 07 52.2  20151230.43  57386.43    20.93  157.1 -15.3
PS15dps     03 22 31.49  +34 36 36.6  20151229.43  57385.43    20.41  155.1 -18.6
PS15dpk     05 09 35.10  +50 09 08.7  20151229.38  57385.38    19.66  158.5 6.0
PS15dpj     05 08 12.38  +51 37 10.2  20151228.44  57384.44    18.45  157.2 6.7
PS15dpd     05 09 58.63  +50 47 09.4  20151228.44  57384.44    20.34  158.0 6.4
PS15dpw     04 10 16.52  +43 35 22.8  20151230.27  57386.27    19.29  156.7 -5.9
PS15dpg     03 17 18.88  +32 20 06.9  20151229.41  57385.41    20.86  155.5 -21.1
PS15dph     03 24 15.04  +30 56 20.1  20151229.46  57385.46    20.17  157.7 -21.4
PS15dpi     03 36 41.65  +35 57 56.4  20151228.52  57384.52    17.62 RR Lyrae; CSS J033641.5+355756
PS15dpp     03 00 39.86  +28 15 25.4  20151228.40  57384.40    20.63  154.7 -26.5
PS15dqb     03 28 34.85  +31 59 08.2  20151230.43  57386.43    19.93  157.8  -20.0 

The following two transients are probable faint AGN/QSO (as previously reported in 
Smith et al. GCN 18786)
PS15dop     03 17 29.58  +29 34 09.2  20151228.40  57384.40    20.01 probable AGN
PS15dpo     02 59 49.56  +25 10 30.4  20151229.25  57385.25    20.55 probable AGN/QSO
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