1984ApJ...278L..75Y Science tional the ""1984. THE Table have greater have than respectively. produce Neugebauer suppress study 7.8, subjective, sources Cluster data over eliminate around arated distinct galaxies detections. Positions on tions report the 1 Abell The The The Netherlands the ASTROPHYSICAL cluster 8.0, the been were 6.0 The noise-equivalent Aeronautics were 1). and the Infrared classical at 60 by than were IRAS the at E. and within American in estimated infrared 2151 rich Hercules field Subject a large-scale and relative A noise Engineering given preliminary extracted middle-infrared µ,m hand the digitally YOUNG, minimum-variance A Flux co-added © the and fits detection source. 4.5 THE et best galaxy made, center total 40 Astronomical Agency is American IRAS map far-infrared al. II. a Hercules survey Astronomical within spikes. relative densities headings: the are an and into cluster. mJy to data. JOURNAL, Cluster. estimates INFRARED OBSERVATIONS (1984). of photographic filtered This using is structure excellent B. each covering the cluster Research results flux-weighted Space for by angular must 41 individual I. results flux in shown T. a Obviously instrument Within to INTRODUCTION Aerospace median Cluster. weighing sources The Society. Satellite have form 0?5 the by a SOIFER, galaxies: If Eight 278:L75-L78, the densities have Administration can Astronomical and simple Abell to of should the Council scanning of an in individual 12, resolution, spiral-rich in X noise grid. no All enhance of the be the a 1 a the observations area brightest was PROPERTIES far-infrared noise Figure have components; AND magnitude rights 25, ?6 number correction Programs signal-to-noise confused 2151. dual F. the thresholding fitted clustering centroids peak field, (SERC). The has in be maps. developed for scan. of J. 60, reserved. RESULTS been signal-to-noise the the 1984 in Low, thresholding treated point 1 galaxies 1. Twenty-four point well final cluster yet Received (NASA), been ?6 for and eleven 60 of the region telescope The (NIVR), Individual In HERCULES March detected sources Printed for X deep the µ,m 17 Society with - and highly of wavelengths whole for G. co-added sources T. 100 this sources 0?5. this eight algorithm described galaxy with infrared: for or 1983September14; main are OF the cluster of is DE ratio immediately NEUGEBAUER, 1 and integrations in unconfused two the µ,m operated Letter, process U.S.A. The brighter. were an the six generally confused at grid Hercules GALAXY observa JONG, tends caution. of ratio the sources US part and greater power of colors. bands 60 • initial source times input maps IRAS these sep sources CLUSTER (see and Na 5.4, ABSTRACT UK Provided µ,m we by by to of of to to is AND Galaxies laws L75 sources to (NGC sources CLUSTERS: M. T. accepted a of No in 30%. Z108-107 of of list et 2151. µ,m using at This Hercules by been scan IRAS emitting logue and galaxies. the shifts estimates level Dressler the tions N. ROWAN-ROBINSON, slope For If The al. Twenty-nine The (ABELL 6045) the the by our the can Tarenghi classified flux are GAUTIER CGCG cannot and dichotomy one Herzog 1983November18 number of used. given direction of for data (1979) remaining sources the Twelve cluster. absolute 12 Hercules 48 contamination be similar in -1.1 50 Galaxies is identifiable (1980) types uses For sources many (which that of Table mJy identified neglected, in of mJy NASA IRAS galaxies, be 2151) 1963, unconfused et as the extrapolates and Table the have Soifer his per is A easily to additional of al. with between threshold. and of in photometric Cluster E quite 1 galaxies galaxy is could and 1 more positions sources the a) square - hereafter the these means a 1 a (1979) OBSERVATIONS or part Astrophysics published 1 2.5. with the a with 14" et the Optical identified Clusters are G. CGCG ?6 striking. SO 60 standard from III. be al. definite classification of is classifications CGCG sources, strongly integral x MILEY, must based on degree an galaxies µ,m late-type in are and part included to Hence, included (1984) DISCUSSION Abell galaxies are 0?5 CGCG). upper field calibration eight Identifications the galaxies notably sources of by await The redshifts. of accurate field deviation statement with galaxies brighter Galaxies, luminosity positions 2152) P. in-scan the who emitting brighter as Dressler galaxies galaxies the limit spiral only in E. in Data centered from redshift of many galaxies general Classifications can of and Dressler absent CLEGG, plate find OF the are Tarenghi to prominent of are have Tarenghi All than galaxies of direction. on be agree Volume 3" than THE members are 6 (1980). CGCG, can types per Dressler's System a as function 108 23" estimated o. measurements. -6". population. associated on density except in the been in 500 a probably positions. square Uncertainties be B with of in et third the the the and association of - et mJy Identifica 2 early-type al. published estimated the the Tarenghi and of Dressler 18 (Zwicky those al. CGCG of weakly (1979), degree (1980) of cross to Abell Cata at mag. have with 0.25 part red For the be 60 of 1984ApJ...278L..75Y L76 1981). galaxy useful standing spiral acquired, note classification the source tion. number been Peterson, Number 34 33 31 23 21 29b 29a 28 27a 2S 17a 18 32 30 26 24 27b 22 20b 20a 16 19 l 13 lSa lSb 10 14 11 12 7b The 8 6 9b 9a 7b 7a s 3 4 2 1 •The cPhotographic blf recent used. that a is as with most Indeed, luminosity 17a, 100 16:02:40 16:0l:S7 16:02:38 16:03:19 16:01:53 16:02:S7 16:02:Sl 16:02:46 16:03:34 16:03:00 16:02: 16:03:06 16:03:20 16:02:55 16:03:23 16:04:21 16:03:2S 16:03:26 16:03:46 16:02:27 16:03:31 16:03:11 16: 16: 16:02:03 16:04:20 16:04:18 16:03:38 16:04:00 16:04: 16:04:02 16:03:32 16:02:27 16:03: 16:03:S8 16:03:31 16: 16: 16: 16: 16: © source Strom, 71 RA(l some conventional the Classifications the 04: 03: 03: 02: 03: 03: 04: µm American star evidence in luminous identified 9SO) infrared reflects 13 15 57 so so 18 18 12 13 11 infrared fluxes and the aspects 15a magnitudes once classification formation Strom catalog (IC in of 16:S7:02 17:06:04 17: 17:20:34 17:21:24 17:22:36 17:00:28 17:0S:47 the Dec 17: 17: 17:28:00 17:26:25 17:34:29 17:29:18 17:33:30 17:43:S9 18:03:47 18:0S:27 18:11:22 18:12:00 18:21:16 18:18:S9 18:28:32 17:29:0S 17:S7:5S 18: 17: 17:3S:OO 1 17:41:26 17:S6:20 18:14:48 18:29:57 18:29:S8 18:34:S9 18:14:00 17:S4:SS 17: 17: 18: 18: a properties infrared in 7: parentheses with morphological of properties ajet sufficiently 1182 02: 1979 Astronomical 21: 12: 14: S3: 51: 54: 30: 02: 23: ( l parentheses history with galaxy 9SO) by 09 46 24 36 01 02 OD S3 32 03 is activity, Sc(B) (Schommer, respectively. = given, zero, Arp source Markarian of of are evolution. of II one, the are (1966) a large the uncertain 12 lOSOO while galaxy galaxy in a galaxy classifications from µm or so 77 16 31 galaxy Dressler's galaxy the Sullivan, two data Society and an 298), the classifications Abell It Flux 4S90 2S can due NGC decimal 142 examination 4S 32 24 4S S6 83 32 34 36 7S 22 from is µm base shows morphological may OBSERVATIONS to be a V important Density 2151 and a peculiar magnitudes 6045. a its possible places in 1290 60 has • prove probe 396 271 23S 207 233 296 12S 107 121 123 130 207 414 104 108 176 118 187 120 743 332 sso lSO 101 120 121 112 120 134 110 signs S4 64 Bothun 88 54 64 64 99 S4 60 96 µm YOUNG forma under Provided field are of been It (mJy)a have the taken SO confusion TABLE ( as of (1200) of (1850) ( to is is <220 <120 <120 5730 <200 <220