J/ApJ/761/34 Kinematical study of the optical ejecta of GK Per (Liimets+, 2012)
A three-dimensional view of the remnant of nova Persei 1901 (GK Per).
Liimets T., Corradi R.L.M., Santander-Garcia M., Villaver E.,
Rodriguez-Gil P., Verro K., Kolka I.
<Astrophys. J., 761, 34 (2012)>
=2012ApJ...761...34L 2012ApJ...761...34L
ADC_Keywords: Novae ; Proper motions ; Radial velocities ; Interstellar medium
Keywords: ISM: jets and outflows; novae, cataclysmic variables;
stars: individual: GK Per; stars: winds, outflows
Abstract:
We present a kinematical study of the optical ejecta of GK Per. It is
based on proper-motion measurements of 282 knots from ∼20 images
spanning 25 years. Doppler shifts are also computed for 217 knots. The
combination of proper motions and radial velocities allows a unique
three-dimensional view of the ejecta to be obtained. The main results
are as follows: (1) the outflow is a thick shell in which knots expand
with a significant range of velocities, mostly between 600 and 1000
km/s, (2) kinematical ages indicate that knots have suffered only a
modest deceleration since their ejection a century ago, (3) no
evidence for anisotropy in the expansion rate is found, (4) velocity
vectors are generally aligned along the radial direction, but a
symmetric pattern of non-radial velocities is also observed at
specific directions, and (5) the total Hα+[N II] flux has been
linearly decreasing at a rate of 2.6% per year in the past decade. The
eastern nebular side is fading at a slower rate than the western side.
Some of the knots were displayed a rapid change of brightness during
the 2004-2011 period. Over a longer timescale, a progressive
circularization and homogenization of the nebula are taking place; (6)
a kinematic distance of 400±30 pc is determined. These results raise
some problems with the previous interpretations of the evolution of GK
Per. In particular, the idea of a strong interaction of the outflow
with the surrounding medium in the southwest quadrant is not supported
by our data.
Description:
Most of the imaging was carried out at the 2.5m Isaac Newton Telescope
(INT) at the Observatorio del Roque de los Muchachos (ORM), La Palma,
Spain. Images were taken with the Wide Field Camera (WFC) and a
narrowband Hα filter having a central wavelength of 6568Å and
a bandpass of 95Å. The pixel scale is 0.33"/pixel.
Other images were taken with the Andalucia Faint Object Spectrograph
and Camera (ALFOSC) at the 2.6m Nordic Optical Telescope (NOT) of the
ORM. An Hα filter (6577/180Å) was used, and the pixel scale
was 0.189"/pixel.
All images were obtained with a seeing better than 1.3" FWHM. We also
searched for archival images of the nebula. See table 1.
Medium-resolution, long-slit spectra of the nebula were obtained
during two observing periods. In 2007 January, the INT+IDS
(Intermediate Dispersion Spectrograph) with grating R1200Y and a 1.5"
slit was used. This configuration covers a spectral range from
5730Å to 7610Å. In 2007 September, the NOT+ALFOSC with grism 17
and 0.5" slit was used, giving a spectral range from 6350Å to
6850Å.
Objects:
----------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------
03 31 12.01 +43 54 15.5 GK Per = NOVA Per 1901
----------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 58 25 Log of the imaging data
table3.dat 82 293 Knots positions, proper motions, and
radial velocities
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See also:
B/cb : Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2014)
B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)
V/123 : Catalog of Cataclysmic Variables (Downes+ 2001-2006)
J/A+A/560/A49 : UV spectra of old novae (Selvelli+, 2013)
J/MNRAS/431/2 : Hα fluxes of Galactic planetary nebulae (Frew+, 2013)
J/PASJ/64/63 : Dwarf novae characterization using SDSS colors (Kato+, 2012)
J/AJ/140/1758 : Spectral atlas of peculiar stars (Tomasella+, 2010)
J/AJ/140/34 : Classification of nova light curves (Strope+, 2010)
J/A+A/420/571 : V1974 Cyg IUE spectroscopy (Cassatella+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 "YYYY-MM-DD" Date Observation date (start of observing night)
11 A1 --- n_Date [R*] Reference image (R), PSF match (*) (1)
12 A1 --- r_Date Reference of publication (2)
14- 23 F10.2 d JD Julian date at the midpoint of observations
25- 34 A10 --- Tel Telescope and Instrument
36- 46 A11 --- Filt Filter (name or λc/FWHM in Å)
48- 51 I4 s Exp [300/7026] Total exposure time
53- 54 I2 --- Nf [1/31] Number of frames added together
56- 58 F3.1 arcsec Seeing [0.2/5] Original seeing
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Note (1): Flag as follows:
R = The image that was used as reference for the astrometry and
flux match of all images.
* = Images from all dates marked with "*" were flux and PSF matched with
the reference image. For 1999 only flux match was done due to its
modest seeing.
Note (2): Reference for published observations as follows:
a = Seaquist et al. (1989ApJ...344..805S 1989ApJ...344..805S).
b = Shara et al. (2012AJ....143..143S 2012AJ....143..143S).
c = Bode et al. (2004ApJ...600L..63B 2004ApJ...600L..63B).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 6 F6.2 arcsec dx ? X (West-East) knot position (1)
8- 13 F6.2 arcsec dy ? Y (North-South) knot position (1)
15- 20 F6.3 arcsec/yr pm [0.007/0.6]?=9.999 Proper motion µ
22- 27 F6.3 arcsec/yr e_pm [0.002/0.07]?=9.999 Error in pm
29- 34 F6.3 arcsec/yr pmX ?=9.999 X component of proper motion
36- 41 F6.3 arcsec/yr e_pmX ?=9.999 Error in pmX
43- 48 F6.3 arcsec/yr pmY ?=9.999 Y component of proper motion
50- 55 F6.3 arcsec/yr e_pmY ?=9.999 Error in pmY
57- 61 F5.1 deg PA ?=999.9 Knot position angle (2)
63- 66 F4.1 deg e_PA ?=9.9 Error in pmPA
68- 72 F5.1 deg pmPA [1/359]?=999.9 Proper motion position angle
α (3)
74- 77 F4.1 deg e_pmPA ?=99.9 Error in pmPA
79- 82 I4 km/s RVel [-989/959]?=9999 Radial velocity with respect
to the systemic velocity (45km/s).
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Note (1): From the central star in the plane of the sky, extrapolated at the
reference epoch (2004-01-29 or JD2453034.37).
9.99 = no detection
Note (2): With respect to the central star as measured (from North to East
counterclockwise) on our reference frame (2004-01-29 or JD2453034.37).
Note (3): In the plane of the sky, measured from North to East counterclockwise.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 06-Aug-2014