J/MNRAS/413/2689 PV Cep V(RI)c and IRAC photometry (Kun+, 2011)
Inner disc rearrangement revealed by dramatic brightness variations in the
young star PV Cep.
Kun M., Szegedi-Elek E., Moor A., Kospal A., Abraham P., Apai D.,
Kiss Z.T., Klagyivik P., Magakian T.Yu., Mezo Gy., Movsessian T.A., Pal A.,
Racz M., Rogers J.
<Mon. Not. R. Astron. Soc., 413, 2689-2695 (2011)>
=2011MNRAS.413.2689K 2011MNRAS.413.2689K
ADC_Keywords: Stars, pre-main sequence ; Photometry, VRI ; Photometry, infrared
Keywords: stars: formation - stars: individual: PV Cep -
stars: pre-main-sequence
Abstract:
Young Sun-like stars at the beginning of the pre-main-sequence (PMS)
evolution are surrounded by accretion discs and remnant protostellar
envelopes. Photometric and spectroscopic variations of these stars are
driven by interactions of the star with the disc. Time-scales and
wavelength dependence of the variability carry information on the
physical mechanisms behind these interactions. We conducted
multi-epoch, multiwavelength study of PV Cep, a strongly variable,
accreting PMS star. By combining our own observations from 2004 to
2010 with archival and literature data, we show that PV Cep started a
spectacular fading in 2005, reaching an IC-band amplitude of 4mag.
Analysis of variation of the optical and infrared fluxes, colour
indices and emission line fluxes suggests that the photometric decline
in 2005-2009 resulted from an interplay between variable accretion
and circumstellar extinction: since the central luminosity of the
system is dominated by accretion, a modest drop in the accretion rate
could induce the drastic restructuring of the inner disc. Dust
condensation in the inner disc region might have resulted in the
enhancement of the circumstellar extinction.
Description:
Photometric observations in the VRcIc bands spanning the time interval
between 2004 September 22 and 2010 November 23 were performed with six
instruments on five telescopes. Most of the data were obtained with
the 60/90/180cm Schmidt telescope of the Konkoly Observatory, equipped
with a Photometric AT 200 camera, and with the 1-m Ritchey-Chretien-
Coude (RCC) telescope of the Konkoly Observatory, equipped with a
Princeton Instruments VersArray:1300B camera. PV Cep was also observed
with the IAC-80 telescope of the Teide Observatory (Spain) between
2009 October 25 and November 7. In 2008 August and 2009 October we
obtained VRI images with the Calar Alto Faint Object Spectrograph
(CAFOS) instrument installed on the 2.2-m telescope of the Calar Alto
Observatory (Spain). On 2010 April 8 we used the Electro Multiplying
(EM) Andor Technology iXonEM+ 888 camera at the RCC telescope of the
Konkoly Observatory.
Objects:
---------------------------------------------
RA (2000) DE Designation(s)
---------------------------------------------
20 45 53.94 +67 57 38.7 PV Cep = HBC 696
---------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 66 16 Comparison stars
table2.dat 60 94 Results of the photometry of PV Cep
table4.dat 73 17 Spitzer photometry for PV Cep
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- --- [C]
2- 3 I2 --- C [1-16] Comparison star number
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 15 F5.2 s RAs Right ascension (J2000)
17 A1 --- DE- Declination sign (J2000)
18- 19 I2 deg DEd Declination (J2000)
21- 22 I2 arcmin DEm Declination (J2000)
24- 27 F4.1 arcsec DEs Declination (J2000)
29- 34 F6.3 mag Vmag Johnson V magnitude
36- 40 F5.3 mag e_Vmag rms uncertainty on Vmag
42- 47 F6.3 mag Rcmag Cousins R magnitude
49- 53 F5.3 mag e_Rcmag rms uncertainty on Rcmag
55- 60 F6.3 mag Icmag Cousins I magnitude
62- 66 F5.3 mag e_Icmag rms uncertainty on Icmag
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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- 7 I7 d JD Julian date
9- 18 A10 "YYYY/MM/DD" Date Observation date
20- 24 F5.2 mag Vmag ?=- Johnson V magnitude
26- 29 F4.2 mag e_Vmag ?=- rms uncertainty on Vmag
31- 35 F5.2 mag Rcmag ?=- Cousins R magnitude
37- 40 F4.2 mag e_Rcmag ?=- rms uncertainty on Rcmag
42- 46 F5.2 mag Icmag ?=- Cousins I magnitude
48- 51 F4.2 mag e_Icmag ?=- rms uncertainty on Vmag
53- 60 A8 --- Tel Telescope
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "YYYY/MM/DD" Date Observation date
12- 15 F4.2 Jy F3.6 ? Color-corrected Spitzer/IRAC flux at 3.6um
17- 20 F4.2 Jy e_F3.6 ? rms uncertainty on F3.6um
22- 25 F4.2 Jy F4.5 ? Color-corrected Spitzer/IRAC flux at 4.5um
27- 30 F4.2 Jy e_F4.5 ? rms uncertainty on F4.5um
32- 35 F4.2 Jy F5.8 ? Color-corrected Spitzer/IRAC flux at 5.7um
37- 40 F4.2 Jy e_F5.8 ? rms uncertainty on F5.7um
42- 46 F5.2 Jy F8.0 ? Color-corrected Spitzer/IRAC flux at 8.0um
48- 51 F4.2 Jy e_F8.0 ? rms uncertainty on F8.0um
53- 57 F5.2 Jy F24 ? Color-corrected Spitzer/MIPS flux at 24um
59- 62 F4.2 Jy e_F24 ? rms uncertainty on F24um
64- 68 F5.2 Jy F70 ? Color-corrected Spitzer/MIPS flux at 70um
70- 73 F4.2 Jy e_F70 ? rms uncertainty on F70um
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 09-Dec-2011