Search Publications
ASASSN-18aan revisited
Nelson, R.; Vagnozzi, A.; Valentini, S.
The light curve of the cataclismic variable ASASSN-18aan is studied using recent observations of the MC589 Observatory, giving an orbital Period and Epoch fully consistent with the data obtained after the discovery are in 2018. Archival data from ASASSN, ZTF and Gaia were used to check if its ares have a quasi-periodic behaviour. A recurrence time…
Variability of L261 in M13
Violat-Bordonau, F.
After the discovery in April 2021 of the variability of the star L199 (now V63), belonging to the globular cluster Messier 13 (NGC 6205), between June and October 2021, we have studied twenty of the brightest stars, excluding the well-known red giant variables: surprisingly a good part of them shows some degree of variability in the range 0.05-0.2…
New Semiregular Variable Star Near The Wizard Nebula - Evolution of the Red Giant MACOMP_V1
Moriconi, M.; Conzo, G.; Marotta, P. G.
The red giant MaCoMP_V1 in Cepheus at coordinates RA (J2000) 22:49:05:49 and DEC (J2000) +57:52:41:6 is a semiregular variable star classified as SRS, number 2225960 in the AAVSO VSX database. Using the Fourier transform, the period P = 24.751(0.062)d was evaluated and, with the support of the ASAS-SN and ZTF surveys, a well-defined light curve wa…
Period Changes of Mira Variables in the M16 - M17 Region
Nesci, R.; Tuvikene, T.; Soszynski, I.
We analyzed the light curves of 165 AGB variables, mostly Miras, in the sky area centered between M16 and M17 (l = 16, b = 0), using the OGLE GVS database in the Ic band. Comparison with the published light curves, derived about 50 years earlier by P. Maffei using Kodak I-N photographic plates, allowed us to find no significant period changes in a…
Five New faint cataclysmic variables from the Zwicky Transient Facility
Bernhard, K.; Lloyd, Ch.
A search of faint, large-amplitude variables in the Zwicky Transient Facility datahas led to the identification of five new CVs. Four of the stars, ZTFJ010013.34+610809.8, ZTFJ051913.86+293006.0, ZTFJ210441.02+394052.7 and ZTFJ210705.14+394617.7 are probably SS Cyg-type systems, while ZTFJ173854.93+175136.3 is a likely SU UMa system.
Confirmation of seven faint ATLAS variable star candidates
Thomas, N.; Guan, C.
A pilot survey conducted at the Lookout Observatory has confirmed seven faint (V ~ 13 to 17) variables in the region of Kepler-76b that were recently discovered by the Asteroid Terrestrial-Impact Last Alert System (ATLAS). The ATLAS survey identified 315,000 probably variables within its wide-field survey in 2018. The faintness (down to r ~ 18) an…
L199, A new variable star in M13
Violat-Bordonau, F.
During a routine study of the variable stars of Messier 13 (NGC 6205 = Cl 1639+365) we have discovered the variability of L199 (TYC 2588-1386-2), a red giant star member of the cluster: using the photometric data - in V band - obtained in the 2019 and 2020 campaigns we have verified its variability. Data from the Zwicky Transient Facility (ZTF) an…
Properties of the recently discovered Eclipsing Binary GSC 03421-01402
Lloyd, Ch.; Screech, J.
GSC 03421-01402 is a low-amplitude eclipsing binary with a period of 7.6800475(44) d. The eclipsing binary is one component of a close pair identified in the Gaia EDR3 data with delta G = 0.45 mag. The light-curve suggests that the primary eclipse is total with an observed depth of 0.13 mag, but due to dilution the true depth could be approximatel…
GSC 03588-09315 is a low-amplitude delta Scuti variable
Boyd, D.; Walker, G.; Lloyd, Ch. +3 more
Time-series observations of GSC 03588-09315 show it is a very low amplitude, multiperiodic delta Scuti variable at the limit of detectability. Five frequencies have been identified at 13.86819(24), 8.10026(79), 5.01966(79), 11.67281(55) and 8.17490(59) c/d with amplitudes of 10, 5, 5, 4, and 3 mmag respectively. The spectral energy distribution of…
The Bright Eclipsing Binary NSV 4031 is not variable
Lloyd, C.; Walker, E. N.; Conner, D. +1 more
Observations of the supposed eclipsing binary NSV 4031 from time-series photometry and data from several synoptic instruments show no evidence of an eclipse or any periodic variation with an amplitude above 0.05 magnitudes. The spectral energy distribution of the star is very closely matched to a spectral type of F5IV.