Conducting the Search.

Any search for supernovae involves a certain amount of persistance, and "hard work". Here are but a few suggestions to assist in making this program one that can be enjoyable as well as productive. VISUAL (for more information on search techniques, see (9) (10). Since there are just ~35 galaxies in the target area that have magnitude referencing (8). It is suggested that the visual observer acquire slides as mentioned in Section 3. or obtain a copy of (6). Then a careful study of the target galaxies should be performed on a regular basis. A limiting magnitude should be established to determine which galaxies will be included in ones personnal program. List of Galaxies where events will be within reach of the visual observer. After careful study and comparison of the various foreground stars has been accomplished over a period of time, one can usually gain a "feeling" of "just" looking at the targets without much reference to charts/photo's. The charts/photo's/slides can then be used for verification if something is spotted or something in the field is suspect. A reference of stars in a particular field of view can also be obtained (if you own a computer) by using (4), or (11) although it is cautioned that while these programs employ the Guide Star Catalog (GSC), many stars in a particular field might be omitted, as the GSC is a limited-yield program....perhaps the enterprising individual could print out the charts (4)(11), and add stars that appear from the eyepiece/photo's of ones particular scope. (also see magnitudes below concerning GSC magnitudes). PHOTOGRAPHIC The enterprising astrophotographer could obtain a base set of the target galaxies by taking short exposures that would reveal a desired depth of stellar magnitude (pretty pictures are not paramount here), plus be able to underexpose the galaxies nucleus (where SN may be residing). Comparisons may then be made visually, or a photographic search can be embarked upon using this technique...this could be a club project where one individual with an astrophotographic setup could provide images (charts) for others visually interested in the search. CCD In this technique the individual could be a "one man gang"....Base images would be important, as in the section above. Comparisons could be made to fields of the target area, this technique would be much quicker, due to the speed of the CCD imaging camera...seconds rather than many minutes. The base "shots" should reveal stars down to the limit of the faintest possible event magnitude (NGC 2693...type II. mag 17.2), although most magnitudes could reach a depth of 16.5 and still be effective. The owner of an automated, computer assisted setup could monitor a large amount of the subject galaxies in any given evening, provided the entities where in a position to do so. A network of conscientious imagers would increase the chances of total, rather than partial coverage of the target area, plus they could act as verifiers if a suspect is spotted. Ongoing programs are currently in existence that are attempting to accomplish the abovementioned task of supernova discovery. Perhaps contacting these individuals could provide an intiative to form a well structured search program. It is important to point out that a scale be known for your photo's, so that accurate offsets from the nucleus can be performed in the event you spot something. MAGNITUDES CCD/photographic/ and visual mags will be different unless transformation formulae are used ie. Here are some formulae that might be of some assistance to the participant: Mpg=B- 0.29+ 0.18(B-V) (Arp,1961)[Photographic usage] (1) V=mpv(isual) -0.3m (Arp, 1961)[Comparison between CCD photometry (V filter) and visual] (2) B=mpg +0.3m +/- 0.2 (Branch and Bettis, 1978)[Blue values] (3) In formula (1) sequencing would have to be obtained, perhaps by implimenting sequenced stars found in (8). Aperture photometry comparison could be used to get a ROUGH estimate of the magnitudes of the stars in a particular field (this method is not recommended by the author, due to the color indices of stars). In formula (2) an adjustment of 0.3m will have to be made in order to avoid addional scatter and the observer's personal equation (visual). Formula (3) would only be used if a blue filter is used and either CCD or photographic techniques were employed. It might also be noted that GSC magnitudes found in (4), and (11) suffer from some disparity and scatter (0.2m-0.6m) this is characteristic of the data and certainly NOT the program that is used to access these stars. Although these magnitudes might be used, when all else has failed...it will at least place the observer..."somewhere in the ballpark"! It should be noted that if any sequencing is done using the GSC, that this fact be noted in any report.... VERIFICATION/REPORTING AN EVENT Finally, it is imperative to have others available who might be able to verify any suspect that you have, either visually, or photographically. Varying locales, and ample observers would provide the best scenario, due to weather conditions, and some cases, time constraints (daylight approaching)...ideally a global network, tied together via electronic communication would be the most desired. These individuals should be well aware of the program, and be reliable. The individual should also possess some knowledge of magnitude estimation, and if possible have enough reference material availed to him/her to be able to make a quick decision regarding the possiblility of an intruder star. Having a friend in the professional astronomical community is a plus. He/she could then make your suspect detection a real possibility via the sophisticated equipment that they have at their disposal. (spectra, photo, larger scopes, etc.) The Internet communication highway is another method to attempt to contact both amateur and professional alike who might share the same desire to find supernovae. It is advised to do this ahead of time so that the excitement of the moment does not "cloud" ones judgement. (This is speaking from personal experience...one does get "excited" when you have spotted a suspect supernova, and you want to be certain that the find is real, so that there is no creditability loss, the two days following my sighting where cloudy). (see IAU Circular #4735) Once a suspect has passed the test as being a bonifide supernova (magnitude estimate, and offset from the galaxies core) event one should contact the Bureau of Astronomical Telegrams with the news (see (8) for details), or if one is a member of one of the many variable star sections, (AAVSO, JAAVSO, BAA) they may offer assistance in getting your suspect (now supernovae) into the proper hands, where spectographic analysis can be performed. Once an event is classified as a bonifide supernova, it would be interesting to follow your find, thru its entire apparition, estimating magnitudes, comprising light curves....this information if forwarded to the many professional institutions around the world, can possibly be used by them in completing work on a particular event. A negative report on any monitoried, or systematic program is also an important research tool (see [12],[13], and [14]). Astronomers can use this data to determine more precisely the extragalactic supernovae rate...a form has been included in the program.(see snform.txt). The galaxy, limiting magnitude, and UT time/date, plus any additional notes can be noted on the form. EPILOGUE A supernova is truly a dynamic event. The ideal scenario in searching for these anomolies is to search in an area that contains many target galaxies ie..... clusters of galaxies. Not only are you able to cover many galaxies in a short period of time, but you are able to accomplish this task in areas that will yield some pretty impressive results (example: The Virgo Cluster yields at least one event per observing year, sometimes more). However, it is the areas that are not being covered that is the theme of this article....by searching an area that is not studded with many entities...thus not many observers, your chances of being the sole discoverer if an event takes place, are pretty high. The statistics and target galaxies in this article are but a small offering that could make for an interesting project. It might also be noted that the area just covering the +50 degree bin is indeed an impressive section of the sky and might in itself present an excellant area to concentrate in the quest for supernovae. However, statistics are what a lot of these and other programs are about and since the area covering +50 to +90 degrees has not been an area where a lot of work has been attempted, it might be worthwhile to concentrate on this area to determine if indeed there are events happening in this region that are going unnoticed. I would estimate that if this area could be diligently monitored for a period of 5 years that some interesting results might be forthcoming in the search for the elusive supernova......Good Luck and Good Hunting!