J/ApJ/826/144 Follow-up observations of SNIa ASASSN-14lp (Shappee+, 2016)
The young and bright type Ia supernova ASASSN-14lp: discovery, early-time
observations, first-light time, distance to NGC 4666, and progenitor
constraints.
Shappee B.J., Piro A.L., Holoien T.-S., Prieto J.L., Contreras C.,
Itagaki K., Burns C.R., Kochanek C.S., Stanek K.Z., Alper E., Basu U.,
Beacom J.F., Bersier D., Brimacombe J., Conseil E., Danilet A.B., Dong S.,
Falco E., Grupe D., Hsiao E.Y., Kiyota S., Morrell N., Nicolas J.,
Phillips M.M., Pojmanski G., Simonian G., Stritzinger M., Szczygiel D.M.,
Taddia F., Thompson T.A., Thorstensen J., Wagner M.R., Wozniak P.R.
<Astrophys. J., 826, 144-144 (2016)>
=2016ApJ...826..144S 2016ApJ...826..144S (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry, ugriz ; Photometry, ultraviolet ;
Spectroscopy
Keywords: galaxies: distances and redshifts; white dwarfs;
supernovae: individual: ASASSN-14lp, Type Ia, NGC 4666, ASASSN-14lp
Abstract:
On 2014 December 9.61, the All-sky Automated Survey for SuperNovae
(ASAS-SN or "Assassin") discovered ASASSN-14lp just ∼2 days after
first light using a global array of 14cm diameter telescopes.
ASASSN-14lp went on to become a bright supernova (V=11.94mag), second
only to SN 2014J for the year. We present prediscovery photometry
(with a detection less than a day after first light) and ultraviolet
through near-infrared photometric and spectroscopic data covering the
rise and fall of ASASSN-14lp for more than 100 days. We find that
ASASSN-14lp had a broad light curve (Δm15(B)=0.80±0.05), a
B-band maximum at 2457015.82±0.03, a rise time of
16.94-0.10+0.11days, and moderate host-galaxy extinction
(E(B-V)host=0.33±0.06). Using ASASSN-14lp, we derive a distance
modulus for NGC 4666 of µ=30.8±0.2, corresponding to a distance
of 14.7±1.5Mpc. However, adding ASASSN-14lp to the calibrating
sample of Type Ia supernovae still requires an independent distance to
the host galaxy. Finally, using our early-time photometric and
spectroscopic observations, we rule out red giant secondaries and,
assuming a favorable viewing angle and explosion time, any
nondegenerate companion larger than 0.34R☉.
Description:
The All-sky Automated Survey for SuperNovae (ASAS-SN, or "Assassin";
Shappee et al. 2014ApJ...788...48S 2014ApJ...788...48S) scans the entire extragalactic sky
in both the northern and southern hemispheres roughly once every 2-3
nights in the V band to depths of 16.5-17.3mag depending on lunation
(Shappee et al. 2016, in preparation). We discovered a new source
(ASASSN-14lp; V∼14.9mag) on 2014 December 9.61 (JDtdisc=2457001.112)
at RA=12:45:09.10, DE=-00:27:32.5 (J2000). There are no pre-explosion
images of this site available in the Hubble Space Telescope (HST)
Archive.
Previous observations were obtained by ASAS-SN 1.25, 7.98, 10.98,
11.97, 15.96, and 18.96 days before discovery (see Table 1 and Figure
1 for details).
The second set of prediscovery images were obtained by K. Itagaki from
2014 November 13 to 2015 January 09 at the Itagaki Astronomical
Observatory, Japan.
After the detection of ASASSN-14lp, we began a multiwavelength,
ground- and space-based follow-up campaign from the X-ray to the
near-infrared (NIR) wavelengths. Swift/UVOT observations were obtained
in V (5468Å), B (4392Å), U (3465Å), UVW1 (2600Å), UVM2
(2246Å), and UVW2 (1928Å). These observations span more than
30days.
Optical ground-based images were obtained with the LCOGT 1m network of
telescopes (gri), the 2m Liverpool telescope (LT) (gri), and the
40-inch Swope telescope (ugri) as part of the Carnegie Supernova
Project II (CSPII; Hsiao et al. 2013ApJ...766...72H 2013ApJ...766...72H).
We obtained an extensive sample of low- and medium-resolution optical
spectra of ASASSN-14lp spanning more than 3 months between 2014
December 10 and 2015 March 16 (see table 2).
Objects:
--------------------------------------------------------
RA (ICRS) DE Designation(s)
--------------------------------------------------------
12 45 09.10 -00 27 32.5 ASASSN-14lp = ASASSN -14lp
--------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 38 465 Photometric observations
table2.dat 70 23 Spectroscopic observations
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See also:
B/eso : ESO Science Archive Catalog (ESO, 1991-2016)
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)
J/MNRAS/444/527 : Tully-Fisher distances for Spitzer galaxies (Sorce+, 2014)
J/AJ/142/156 : The CSP (DR2): photometry of SNe Ia (Stritzinger+, 2011)
J/ApJ/731/120 : Intrinsic SN Ia light curves (Mandel+, 2011)
J/AJ/139/519 : Carnegie supernova project. SNe Ia (Contreras+, 2010)
J/AJ/139/120 : Low-redshift Type-Ia supernovae (Folatelli+, 2010)
J/ApJS/172/599 : SFI++ II. A new I-band Tully-Fisher catalog (Springob+, 2007)
http://www.astronomy.ohio-state.edu/~assassin/index.shtml : ASAS-SN home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 F8.3 d JD Julian Date of observation; JD-2450000
10- 14 A5 --- Band Band used in the observation (u,g,r,i,V, UVM2,
UVW2 or clear)
16 A1 --- l_mag Limit flag on mag
18- 22 F5.2 mag mag [11.9/19] Observed magnitude in Band
24- 27 F4.2 mag e_mag [0.01/0.5]? Uncertainty in mag
29- 38 A10 --- Tel Telescope where observation was taken (1)
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Note (1): Telescope as follows:
Swift = NASA Swift γ-ray burst satellite mission;
CSP = Carnegie Supernova Project II on 40-inch Swope telescope;
LCOGT = Las Cumbres Observatory Global Telescope Network;
LT = 2-m Liverpool telescope;
ASAS-SN/bd = All-Sky Automated Survey for SuperNovae North, "Brutus";
ASAS-SN/bf = All-Sky Automated Survey for SuperNovae South, "Cassius";
Itagaki = Itagaki Astonomical Observatory, Japan 0.30m f/8 reflector.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 14 A14 "Y/M/D" Date UT date of observation
16- 24 F9.3 d JD Julian date of observation; JD-2400000
26- 30 F5.1 d t-tfirst [3.2/98.9] Time after first light
(tfirst=2456998.88-0.10+0.11)
32- 36 F5.1 d t-tBmax [-13.8/82] Time after B-band maximum
(tBmax=2457015.82±0.03)
38- 52 A15 --- Tel Telescope/Instrument
54- 57 I4 0.1nm lambda1 [3200/4200] Lower wavelength range (in Å)
58 A1 --- --- [-]
59- 63 I5 0.1nm lambda2 [6850/10000] Upper wavelength range (in Å)
65- 70 F6.1 s Exp [180/1800] Exposure time
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 28-Sep-2016