[vsnet-chat 1567] Update of +50 to +90 Supernovae Search

["Steve H. Lucas" <76620.1721@compuserve.com>]

January 21,1999                              STARBURST                     
                                  N0.2
        
          (NEWSLETTER OF THE INTERNATIONAL SUPERNOVAE NETWORK)
                          BY STEVE H. LUCAS
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UPDATE OF +50 TO THE POLE PROJECT IN SEARCH OF SUPERNOVAE (1995-1998)

FORWARD:

The program SUNSRCH.ZIP (Pole 1 and II) has been presented to the
International Supernovae Network to aid the prospective supernovae hunter
in detecting extragalactic supernova events in a controlled area of from
+50 degrees to the Pole. A comprehensive study of the "Shapley-Ames Catalog
of Bright Galaxies" within the control area indicates that there are
approx. 302 galaxies of varying types brighter than magnitude 13.4.

RESULTS OF 1998:

Thirteen supernovae events were discovered in 1998 within the declination
bins of +50 to +90 degrees. Of the total - five were found by amateur
astronomers, with one inspired amateur compiling four events with an
automatic supernovae search of his own initiative [SNe 1998cl, 1998cn,
1998cp, 1998di] (Michael Schwartz). 

Michael Swartz (amateur automatic search)- 4
Lick Observatory SNe Search- 4
BAO (Bejing Astronomical Observatory) Supernova Search- 2
Jean Mueller- 2
Mark Armstrong (UK Nova and SNe Patrol)- 1
 

RESULTS 1995-1998:

Forty-six supernovae events (46) (involving varying galaxy magnitude
ranges) have been found within a four year period within the declination
bins of +50 - +90 degrees (December, 1994 - December, 1998). A total of
twelve events have been found (Part 1 and Part II) by amateur astronomers,
with one being shared with professionals (1996cc). (SNe 1995E, 1996bk,
1996bu, 1996cc, 1997E, 1997bq, 1997cx, 1997da, 1997db, 1997ei, 1998aq, and
1998cn).

(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 mentioned 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. One Hundred and twenty-four
(124) additional galaxies appear within the same field as the control
target entities (~15' field) and may be used by CCD/deep photographic
search initiatives. 


CATALOGED SUPERNOVAE IN THE CONTROL AREA (1885-1998):

To date (December 31, 1998) ~1400 (+/-) SNe events have been cataloged
since 1885. The total events occuring within the +50 - 90 degree
declination bin (all galaxy magnitude ranges) is 158 (+/-), yielding a
percentage find of 11.28%. The events (13) in 1998 accounted for 08.17%,
(159 total events+/-) which is much smaller than the over-all percentage
rate. (This might indicate that this area was not a priority this year as
compared to previous years where the percentage was much higher--SHL.)

+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, 1998T, 1998aq, 1998cp, 1998di, 1998ec, 1998en, 1998et, 1998dx.

+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, 1998bm, 1998eb, 1998ex. 

+70

1972H, 1978F, 1985A, 1987M, 1989D, 1995E, 1995X, 1995ag, 1997E, 1997bq,
1997ct, 1997db, 1998cl, 1998cn.

+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     +60     +70     +80 -+90

           97      37       14            10

This yields a percentage find of:

61.39% of SNe occuring in the +50 dec. bin. 
23.41% of SNe occuring in the +60 dec. bin. 
08.87% of SNe occuring in the +70 dec. bin.
06.33% of SNe occuring in the +80-+90 dec. bin. 

DISCUSSION:

*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. 

*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.
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 four 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)
January, 21, 1999
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REFERENCES:

Shapley-Ames Catalog: (Carnegie Inst. of Washington, 1981)

Third Revised Catalog of Galaxies (RC3): Harold G. Corwin,[machine-readable
version](CalTech, Ca, 1991)

Megastar Sky Program: E.L.B. Software, 8910 Willow Meadow, Houston,TX.
77031(private correspondance)(current version).

David Bishop's Supernovae Page:
(http://vsnet.ggw.org/asras/supernovae.html)

Michael Richmond's Home Page:
(http://a188-L009.rit.edu/richmond/)

VSNET Home Page

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