J/ApJ/755/158 Near-IR interferometry of nova Vul 2007 (Rajabi+, 2012)
Spectro-interferometric observations of classical nova V458 Vul 2007.
Rajabi S., Muterspaugh M.W., Lane B.F., Sirk M.M., Browne S.,
Ghasempour A., Halverson S.P., Kelly J.G., Williamson M.
<Astrophys. J., 755, 158 (2012)>
=2012ApJ...755..158R 2012ApJ...755..158R
ADC_Keywords: Interferometry ; Novae ; Infrared sources
Keywords: novae, cataclysmic variables; techniques: interferometric
Abstract:
We used the Palomar Testbed Interferometer (PTI) to resolve 2.2µm
emission from the classical nova V458 Vul 2007 over the course of
several days following its discovery on 2007 August 8.54 UT. We also
obtained K-band photometric data and spectra of the nova during the
early days of the outburst. We also used photometric measurements from
the AAVSO database. This is a unique data set offering a
three-technique approach: high-resolution imaging, spectroscopy, and
photometry. Our analysis shows that the nova ejecta can be modeled as
an inclined disk at low inclination, i.e., low ellipticity which is
consistent with the nova being in the fireball phase at which the
outflowing gas is optically thick, confirmed by the presence of strong
P-Cygni Balmer lines in the spectra. The expansion velocity is
~1700km/s, derived from the Hα line. By combining the
nova's angular expansion rate measured by PTI with the expansion rate
measured from spectroscopy, the inferred distance to the nova is
9.9-11.4kpc. We also used the K-band fluxes and the derived size of
the emission to estimate the total mass ejected from the nova
~4x10-4M☉. The quick transition of the nova from Fe II
to He/N class makes V458 Vul 2007 a hybrid nova.
Description:
Nova V458 Vul was observed with the PTI (Palomar Testbed
Interferometer) in the NIR at 2.2um wavelength for nine nights between
2007 August 10 and 2007 August 21 (table 1).
During the early days of explosion in 2007 August (10, 11, 13 and 15),
we obtained high dispersion wide bandpass spectra of the nova from the
Hamilton Echelle Spectrometer using the CAT at Lick Observatory
(R=20000-60000 covering 4000-9800Å) .
Objects:
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RA (2000) DE Designation(s)
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19 54 24.61 +20 52 52.6 NOVA Vul 2007 = V* V458 Vul
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 64 99 Log of the interferometric observations
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See also:
J/AZh/88/34 : Long-term (1984-2008) JHKLM phot. of stars (Shenavrin+, 2011)
J/ApJS/197/31 : Swift X-ray observations of novae. II. (Schwarz+, 2011)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 F11.5 d MJD Modified Julian Date of the observation
13- 19 F7.5 um lambda [2.19/2.26] Wavelength (K-band)
21- 22 A2 --- BL [NSW] Baseline (NorthWest, North-South or
SouthWest)
24- 33 F10.6 m u Projected u baseline
35- 45 F11.6 m v Projected v baseline
47- 54 F8.6 --- V2 [0.43/1.1] Squared visibility
56- 64 F9.7 --- e_V2 Uncertainty in V2
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 12-Mar-2014