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J/A+A/604/A48       UBVRI photometry and line fluxes of AG Peg   (Skopal+, 2017)

New outburst of the symbiotic nova AG Peg after 165 years. Skopal A., Shugarov S.Yu., Sekeras M., Wolf M., Tarasova T.N., Teyssier F., Fujii M., Guarro J., Garde O., Graham K., Lester T., Bouttard V., Lemoult T., Sollecchia U., Montier J., Boyd D. <Astron. Astrophys. 604, A48 (2017)> =2017A&A...604A..48S (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, cataclysmic ; Photometry, UBVRI ; Energy distributions ; Spectroscopy Keywords: binaries: symbiotic - novae, cataclysmic variables - stars: individual: AG Peg Abstract: AG Peg is known as the slowest symbiotic nova, which experienced its nova-like outburst around 1850. After 165 years, during June of 2015, it erupted again showing characteristics of the Z And-type outburst. The primary objective is to determine basic characteristics, the nature and type of the 2015 outburst of AG Peg. We achieved this aim by modelling the spectral energy distribution using low-resolution spectroscopy (330-750nm), medium-resolution spectroscopy (420-720nm; R=11000), and UBVRCIC photometry covering the 2015 outburst with a high cadence. Optical observations were complemented with the archival HST and FUSE spectra from the preceding quiescence. During the outburst, the luminosity of the hot component was in the range of 2-11x1037(d/0.8kpc)2erg/s. To generate the maximum luminosity the white dwarf (WD) had to accrete at ∼3x10-7M_☉/yr, which exceeds the stable-burning limit and thus led to blowing optically thick wind from the WD. We determined its mass-loss rate to a few x10-6M_☉/yr. At the high temperature of the ionising source, 1.5-2.3x105K, the wind converted a fraction of the WD's photospheric radiation into the nebular emission that dominated the optical. A one order of magnitude increase of the emission measure, from a few x1059(d/0.8kpc)2/cm3 during quiescence, to a few x1060(d/0.8kpc)2/cm3 during the outburst, caused a 2mag brightening in the LC, which is classified as the Z And-type of the outburst. The very high nebular emission and the presence of a disk-like HI region encompassing the WD, as indicated by a significant broadening and high flux of the Raman-scattered OVI 6825Å line during the outburst, is consistent with the ionisation structure of hot components in symbiotic stars during active phases. Description: Multicolour photometry in the standard Johnson-Cousins UBVRcIc system of the symbiotic star AG Peg covering its 2015 outburst is presented in Table 1. Individual measurements represent the night mean values and were obtained by a photoelectric photometer (PP) or using a CCD camera (CCD). Table 6 introduces fluxes of selected emission lines: HeII 4686Å, H-beta, H-alpha and the OVI Raman scattered line at 6825Å in units of 10-11erg/s/cm2. Objects: ------------------------------------------------- RA (2000) DE Designation(s) ------------------------------------------------- 21 51 01.97 +12 37 32.1 AG Peg = V* AG Peg ------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 57 65 Observed UBVRcIc magnitudes of AG Peg table6.dat 66 48 Dereddened fluxes for HeII 4686Å, H-beta, H-alpha and OVI Raman line 6825Å
See also: J/A+A/317/712 : UV fluxes and electron density of AG Peg (Altamore+ 1997) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 11 F11.3 --- JD Julian date (JD-2400000) (UT) 12- 19 F8.3 mag Umag ?=999 U magnitude (1) 20- 27 F8.3 mag Bmag ?=999 B magnitude (1) 28- 35 F8.3 mag Vmag ?=999 V magnitude (1) 36- 43 F8.3 mag Rcmag ?=999 Rc magnitude (1) 44- 51 F8.3 mag Icmag ?=999 Ic magnitude (1) 52- 57 A6 --- Phot Type of photometry (2)
Note (1): the value of 999.000 means that no measurement is available Note (2): Type of photometry as follows: PP = Photoelectric photometry CCD = CCD photometry
Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 14 A14 --- Date Date in the form: YYYY/MM/DD.ddd (UT) 15- 25 F11.3 --- JD Julian date (JD-2400000) (UT) 26- 32 F7.2 10-14W/m2 HeII ?=0 HeII 4686Å line flux (1) 33- 39 F7.2 10-14W/m2 Hbm ?=0 H-beta flux measured (1) 40- 46 F7.1 10-14W/m2 Hbt ?=0 H-beta flux corrected for absorption (1) 47- 53 F7.1 10-14W/m2 Ham ?=0 H-alpha flux measured (1) 54- 60 F7.1 10-14W/m2 Hat ?=0 H-alpha flux corrected for absorption (1) 61- 66 F6.2 10-14W/m2 Ram ?=0 Raman scattered OVI 6825Å flux (1)
Note (1): All fluxes are dereddened with E(B-V)=0.1mag. The value of 0.0 means not available or saturated measurement
Acknowledgements: Augustin Skopal, skopal(at)
(End) Augustin Skopal [AI SAS, Slovakia], Patricia Vannier [CDS] 29-May-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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