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Variable stars, recent observations. Dr. F.-J. (Josch) Hambsch. Interests. Cataclysmic variables (VSNET, CBA) RR Lyrae stars (possibly with Blazhko effect) High Amplitude Delta Scuti (HADS) Discovery of new variable stars (Pretty pictures). Observatory in Mol, Belgium.
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Variable stars, recent observations Dr. F.-J. (Josch) Hambsch
Interests • Cataclysmic variables (VSNET, CBA) • RR Lyrae stars (possibly with Blazhko effect) • High Amplitude Delta Scuti (HADS) • Discovery of new variable stars • (Pretty pictures)
Observatory in Mol, Belgium • Several scopes (C14, C11, 40cm f/8, 20cm f/8) • STL11K, ST10, ST8 CCD with BVRI photometric filters • Usage each clear night (if at home) Furthermore, access to scopes in NM, Australia and in planning a remote Site in Chile with 40cm f/6.8
CV‘s • YZ Cnc • BK Lyn • ER UMa • SDSS1339+4847 • ....
ER UMa More than 100 d observations ~ 8000 images
TT Ari max and minimum view Source: H.-G. Dietrich (BAV)
RR Lyrae stars • NSVS 7454553 • GV And • TU Com • NU Aur • ....
E = 2455624.25 HJD P = 0.52186 +/- 0.00018 d NSVS 7454553 Blazhko Effect !!
E = 2455460.955 HJD P = 0.52813 +/- 0.00012 d GV And Blazhko Effect !!
E = 2455528.9335 HJD P = 0.46187 +/- 0.00002 d TU Com Blazhko Effect !!
E = 2455087.44 HJD P = 0.53940 +/- 0.00002 d NU Aur Blazhko Effect !!
NU Aur Blazhko period 114.7 d
E = 2455602.945 HJD P = 0.46296 +/- 0.00008 d VY CrB Blazhko Effect !!
VY CrB Blazhko period 33.4 d
E = 2455470.615 HJD P = 0.5965 +/- 0.013 d DY And Blazhko Effect !!
DY And Blazhko period 224.8 d
CX Lyr Blazhko period 68.04 d
Properties of YY Boo Algol type eclipsing binary Discovered by Hoffmeister in 1949 Spectral type : F9IV Period of eclipses: 3.933049 d Candidate oscillating eclipsing binary according to Mkrtichian et al. 2004 based on spectral type But not in list of candidate oEA‘s
B, V filter Light curve Pulsations subtracted according to Frequencies determined
Properties of YY Boo Oscillations typical for a Delta Scuti type variable Period of oscillations: ~ 88 min 2nd largest pulsation amplitude among oEA stars after BO Her Results published in IBVS 5949 Spectroscopic studies under way
Conclusions • CV‘s have been recently the main observing targets based on VSNET and CBA alerts • Intensive follow-up of RR Lyr stars with Blazhko effect mainly from NM • Collaboration with P. Wils, P. De Ponthiere and J. Vandenboere