SN Searching from +50 to the Pole - Part 3.
Searching For Supernovae In Areas Normally Not Covered By
Conventional Searches.
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FORWARD The program Sunsrch.zip (Pole # 1) was presented to the International Supernovae Network on 1/9/95 to aid the prospective supernovae hunter in detecting extragalactic supernova events in a controlled area of from +50 degrees to the Pole. Here is a updated summary of that program. THE PROGRAM (Part 1) A study of the "Shapley-Ames Catalog of Bright Galaxies" in the control area indicate that there are approx. 130 galaxies of varying types brighter than 12.5m, which would put these galaxies within the realm of the amateur astronomer with a moderate-sized telescope. RESULTS OF PART I Thirteen supernovae events (involving varying galaxy magnitude ranges) were found within a two year period in the declination bins of +50 - +90 degrees (December, 1994 - December, 1996). Four events (within the parameters of Part 1 of this program) were found by amateur astronomers, with the latter being shared with professionals (SNe 1995E, 1996bk, and 1996bu, and 1996cc). In addition nine events (SNe 1995F, 1995J, 1995O, 1995X, 1995ag, 1996ah, 1996bn, 1996bv and 1996by) were found which were fainter than the limitations of this program. LAST YEAR PART II (POLE 2) WAS IMPLEMENTED. HERE IS AN OVERVIEW OF THAT PROGRAM In the second installment of searching for supernovae (SNe) from +50 to the Pole an additional 172 target galaxies will be added to the program. These galaxies will be brighter than magnitude 13.4, (but fainter than 12.5m as per Part 1 of this program) and are gleaned from the Shapley-Ames Catalog (Appendix A) (Note: The magnitudes of some of the entities have had more updated values associated with them, hence they might fall outside of the limitations of the catalog data). It is the intent of this program to extend the capabilities (or limiting magnitude) of target galaxies to those visual observers who possess larger aperture scopes. These, and any additional galaxies (124) that appear within the same field as the target entities (~15' field) may also be used by CCD/deep photographic search initiatives. RESULTS OF 1997 There were 20 SNe discovered (involving varying galaxy magnitude ranges) in the declination bins of +50 to +90 in 1997. Six events were found by amateurs (SN's 1997E, 1997bq, 1997cx, 1997da, 1997db, and 1997ei), and 14 events were found by others (SN's 1997T, 1997Y, 1997bm, 1997ca, 1997cb, 1997cc, 1997ch, 1997ci, 1997cj, 1997ct, 1997di,1997ea, 1997ff, and 1997fg). Of the events found, three fell within the parameters of the +50 to the Pole project [Parts I and II] (SN1997e in NGC 2258, SN1997bq in NGC 3147, and SN1997ei in NGC 3963). Thus far seven events have been found in the control area since its inception (Parts I and II). (NOTE: In 1997 the successes of an automated amateur SNe search were realized....Michael Schwartz of Oregon discovered three catalogued events as a result of his efforts. We hope to see many more discoveries from this inspired searcher). Events by Order of Declination: +50 ( 7 ) +60 ( 7 ) +70 ( 4 ) +80 ( 2 ) Types of Events: Type Ia ( 8 ) Type I? ( 1 ) Type II ( 5 ) Unclas. ( 6 ) CATALOGED SUPERNOVAE IN THE CONTROL AREA (1885-1997) To date (December 31, 1997) ~1241 (+/-) SNe events have been cataloged since 1885. The total events occuring within the +50 - 90 degree declination bin (all galaxy magnitude ranges) is 145 (+/-), yielding a percentage find of 11.68%. The events (20) in 1997 accounted for 12.26%, (163 total events) which is a bit higher than the over-all percentage. +50 1909A, 1912A, 1917A, 1937A, 1939C, 1940A, 1940C, 1940D, 1946A, 1948B, 1951H, 1953G, 1953H?, 1954C, 1955A, 1955E, 1956A, 1957A, 1963J, 1963K, 1963O, 1964A, 1964E, 1964O(INTERGAL?), 1965L, 1965O, 1968D, 1968J, 1969B, 1969P, 1970E, 1970F, 1970G, 1972B, 1972R, 1973C, 1973V, 1974C, 1974D, 1975E, 1975G, 1975T, 1976C, 1976M?, 1978B, 1978H, 1979B, 1980B, 1980D, 1980K, 1982W, 1983B, 1982X, 1983W, 1984B, 1984Q, 1987C, 1988L, 1988N, 1988R?, 1990??, 1991F, 1991G, 1991N, 1991Y?, 1992B, 1992F, 1992R, 1992ac, 1992aw, 1992bm. 1992bt, 1992bu, 1993G, 1993ai, 1994E, 1994G, 1994J, 1994P, 1995F, 1996bu, 1996bv, 1997Y, 1997bm, 1997ca, 1997cb, 1997cc, 1997ea, 1997ei. +60 1950M, 1954J, 1954K, 1971M, 1972G, 1976N?, 1977C, 1982Y, 1985H, 1988J?, 1989P?, 1989X?, 1991ae, 1991an, 1991au, 1991aw, 1992aa, 1992av, 1993J, 1993ac, 1994A, 1994W, 1995J, 1995O, 1996bk, 1996bn, 1996by, 1997ch, 1997ci, 1997cj, 1997da, 1997di,1997ff, 1997fg. +70 1972H, 1978F, 1985A, 1987M, 1989D, 1995E, 1995X, 1995ag, 1997E, 1997bq, 1997ct, 1997db,. +80 1962Q, 1968V, 1968W, 1977E, 1982B, 1987L,1993X, 1996ah, 1997T, 1997cx. The total breakdown of supernovae in the control declination bins are as follows (Since 1885): +50 ( 89 ) +60 ( 34 ) +70 ( 12 ) +80 ( 10 ) +90 This yields a percentage ratio of: 61.4% of SNe occuring in the +50 dec. bin. (down 3.4% from 1996) 23.4% of SNe occuring in the +60 dec. bin. (up 0.8%) 8.3% of SNe occuring in the +70 dec. bin. (up 2%) 6.9% of SNe occuring in the +80-+90 dec. bin. (up .6%) DISCUSSION The year 1997 was one of the most productive for SNe events discovered. Some of the key players in the game were: Supernova Cosmology Project- 47 events* High Z SN Project- 39 Mt Stromlo Abell Cluster SN Search Team- 18 Beijing Astronomical Observatory SN Initiative- 15 Eros Project- 10 Masakatsu Aoki- 4 Jean Mueller- 4 Michael Swartz- 3 UK Nova and SN Patrol- 2 (* To learn about research being conducted by this search project see: ApJ.,_483_:565-581, July, 10, 1997, Perlmutter et. al, "Measurements of the Cosmological Parameters From the First Seven SNe at z=>/_ 0.35"). It might be worthy to mention here that 17 events in 1997 discovered by this search team were fainter than magnitude 20.0! This Project has developed a technique "that allows discovery of high redshift SN Ia's in groups of 10 or more 'batch' discoveries at one time. Follow-up spectroscopy and photometry is then be conducted". Also see: Perlmutter in "Thermonuclear Supernovae", ed. P. Ruiz-Lapuente, R. Canal, & J. Isern (Dordrecht:Kluwer _749_, (1997), ApJ.,_440_,L41(1995), and IAUC #6270). This author has championed this area of study and proposes substantial event possibilities if a concentrated search initiative were undertaken for this area, and that once found, these events could be monitored for a longer period of time and be more accessible to uninterrupted research, due to their location. SOME THOUGHTS....... *Monitor the target galaxies, at various windows of opportunity, at least twice per month. *Become familiar with the Galactic star field, so instant recognition of any intruder star will become apparent. *In programs involving CCD imaging devices....take "base images" to compare with later monitorings of a particular galaxy. *After careful scrutiny of a new suspect (checking for asteroids, variable stars, HII regions, etc.) request confirmation of the suspect from the International Supernovae Network or VSNET alert forums and follow the guidelines presented by the Webmasters there to determine if your suspect is a bonafide supernova. (NOTE: Dr. Michael Richmond has provided a tool, with cooperation of the Central Bureau of Astronomical Telegrams to help determine if an asteroid/s might be present near a galaxy when a suspect supernova is sighted. The service can be found on Mr. Richmond's Home Page [below in references]. Click on "List of Supernovae", then click on "Tool for Checking for Minor Planets Near Suspected SN". Many thanks to Dr. Richmond and CBAT for providing this utility to SN searchers). *Although no figures are available on the negative observations that occured in this area during the past three years (to indicate a SNe "hit rate"), I would have to infer that the rate would be considerably improved if more discipled visual/CCD searching in this area were undertaken. Good luck and good Hunting..... Steve H. Lucas (e-mail:76620.1721@compuserve.com) December 31, 1997 (Revised April 27, 1998) ************************************************************************** REFERENCES Shapley-Ames Catalog: (Carnegie Inst. of Washington, 1981) Michael Richmond's Home Page: http://a188-l004.rit.edu/richmond/index.html http://a188-l004.rit.edu/richmond/sne/sne.html Third Revised Catalog of Galaxies (RC3): Harold G. Corwin,[machine-readable version](Cal Tech, Ca, 1991) Megastar Sky Program: E.L.B. Software, 8910 Willow Meadow, Houston,TX. 77031(private correspondance)(current version). Asiago Supernovae Catalog: [machine-readable version](Univ. of Padova, Asiago, Italy, 1996) Sternberg Master SNe List: [machine-readable version](Sternberg Astronomical Institute, Moscow, Russia 1997) |