114 TV CORVI (UGSU) Range: 13.0-19.0V Position: 12 20 24.19 -18 27 02.1 (J2000, from .dat file) Magnitude: V=19.026 B-V=0.109 (Henden, single night) ID RA (2000) DEC X Y N V ERR B-V ERR a) Comparison star sequence 1 1 12 20 29.3 -18 31 20 72 -258 4 12.281 0.041 0.766 0.036 2 12 20 05.8 -18 21 17 -263 345 4 14.054 0.012 0.778 0.008 3 12 20 10.7 -18 23 41 -192 201 4 14.528 0.011 0.585 0.008 4 12 20 21.9 -18 27 41 -32 -39 4 14.660 0.011 0.632 0.010 5 12 20 13.4 -18 25 53 -154 69 4 14.824 0.012 0.899 0.002 6 12 20 27.2 -18 26 42 42 20 4 14.930 0.014 1.443 0.015 7 12 20 32.3 -18 28 59 115 -117 4 15.171 0.013 0.712 0.006 8 12 20 35.2 -18 25 28 157 94 4 15.606 0.011 0.806 0.007 9 12 20 16.9 -18 30 14 -104 -192 4 15.856 0.011 0.667 0.011 10 12 20 08.5 -18 26 43 -223 19 4 16.314 0.031 0.660 0.023 11 12 20 21.2 -18 25 14 -43 108 4 16.505 0.013 0.685 0.022 12 12 20 25.2 -18 24 47 14 136 4 17.271 0.025 0.822 0.033 13 12 20 13.6 -18 28 48 -151 -106 4 17.838 0.019 0.582 0.015 14 12 20 22.1 -18 26 37 -30 25 3 18.557 0.032 0.680 0.034 b) Wide-colour extension for CCD calibration 12 20 44.2 -18 24 32 284 150 4 17.180 0.029 0.523 0.039 12 20 18.4 -18 29 30 -82 -148 4 15.770 0.012 0.557 0.013 12 20 47.8 -18 21 04 336 358 4 17.054 0.024 1.394 0.042 12 20 32.7 -18 26 36 122 26 3 17.612 0.006 1.528 0.078 Notes: 1. There is another photoelectric sequence for this variable determined by Pam Kilmartin (Publ. VSS RASNZ, No. 16, 1991). Her sequence nicely fills the gap between 12.3 and 14.1 in the above sequence. Kilmartin's sequence is shown on VSS RASNZ chart 1106, dated 03/1995. There is one star in common between Kilmartin's sequence and the sequence shown here. 2. The AAVSO preliminary chart, revision 3, dated 01/1996 shows some photoelectric values derived by Richard Stanton, as well as Kilmartin's magnitudes. The Stanton and Kilmartin magnitudes agree to within 0.1V. Two of Stanton's magnitudes are common with the sequence shown here: ID Henden Kilmartin Stanton V B-V V B-V V 1 12.281 0.766 12.39 0.77 4 14.660 0.632 14.6 6 14.930 1.443 14.8 3. It is to be noted that Kilmartin's stars 'b' and 'd' (not part of this sequence), which are both shown on the AAVSO and the RASNZ chart as 121 and 114 respectively, were transposed during the original reduction (Kilmartin, private communication, June 1999). Additionally 'd' shown as 114 is actually the galaxy PGC 39839. To rectify these mistakes, change 121 to 114 and delete 114 and mark it as a faint galaxy. 4. Superhumps were observed during the February 2001 superoutburst with a period of 0.06492 days (vsnet-campaign 795). 5. This variable star was discovery by Clyde Tombaugh in 1931 but only recently determined to be a dwarf nova (Levy, et al. 1990, IAUC 4983). Shown as Crv1 in Downes and Shara (1993). 6. Minimum magnitudes vary from V=18.8 to V=19.0. Bruce Sumner Revised 11 June 1999