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ALABAMA University Libraries THE UNIVERSITY OF ALABAMA University Libraries The IC 342/Maffei Group Revealed Ronald J. Buta – University of Alabama Marshall L. McCall – York University, Canada Deposited 06/11/2019 Citation of published version: Buta, R., McCall, M. (1999): The IC 342/Maffei Group Revealed. The Astrophysical Journal Supplement Series, 124(1). DOI: 10.1086/313255 © 1999. The American Astronomical Society. All rights reserved. THE ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 124:33È93, 1999 September ( 1999. The American Astronomical Society. All rights reserved. Printed in U.S.A. THE IC 342/MAFFEI GROUP REVEALED RONALD J. BUTA1 University of Alabama Department of Physics and Astronomy, Tuscaloosa, AL 35487-0324; buta=sarah.astr.ua.edu AND MARSHALL L. MCCALL1,2 York University Department of Physics and Astronomy, 4700 Keele Street, Toronto, Ontario, Canada, M3J 1P3; mccall=yorku.ca Received 1998 November 30; accepted 1999 April 27 ABSTRACT Deep wide-Ðeld CCD images in the optical and near-infrared have been acquired for 14 of the 16 known or suspected members of the IC 342/Ma†ei Group of galaxies, one of the closest groups to the Milky Way, and probably the closest group to M31. Because of their low Galactic latitude, all galaxies are heavily extinguished, and myriads of foreground stars are superimposed. A sophisticated algorithm built around DAOPHOT has been developed which successfully removes the foreground stars, making possible comprehensive morphological and photometric studies. The cleaned near-infrared images reveal the true morphology and extent of many of the galaxies for the Ðrst time, three of which are among the largest in the northern sky. Besides surface brightness proÐles, precise total magnitudes and colors have been measured. Many of the results represent substantial revisions to previous estimates. The data will make possible new determinations of the distances and masses of the galaxies, which are crucial for evaluating the impact the group may have had upon the dynamical evolution of the Local Group. Subject headings: galaxies: clusters: individual (IC 342/Ma†ei) È galaxies: photometry È galaxies: structure È infrared: galaxies 1. INTRODUCTION ellipse Ðts to isophotes, orientations, and spheroid and disk properties. In a separate paper, we will undertake a com- The IC 342/Ma†ei Group is a loose grouping of more prehensive analysis of foreground extinctions, which may be than a dozen galaxies located behind the Milky Way near up to a factor of 100 in the V band for several group the northern intersection of the Galactic and supergalactic members, and then derive distances using a variety of well- planes. The group is thought to be one of the most impor- established techniques. tant within 5 Mpc of the Milky Way and may contain the In ° 2, we present some background information to place nearest normal giant elliptical. Yet, deÐnitive estimates of our observations into proper perspective. Following this, in its total mass and population have never been obtained, ° 3, we discuss the processing and calibration of the Schmidt owing to severe extinction and the superposition of myriads images. In ° 4, we describe how images were cleaned, includ- of foreground stars. To date, the best available estimates for ing the method developed to eliminate foreground stars, the distance are in the range of 2È4 Mpc. If correct, dynami- which posed a formidable obstacle to photometry for most cal studies suggest that the two dominant members, IC 342 of our sample galaxies. An atlas of the galaxies, showing and Ma†ei 1, may have interacted with the Local Group as morphology before and after elimination of Ðeld stars, is recently as eight billion years ago. Clearly, the group merits presented in ° 5. Surface photometry, including the deriva- far more attention than it has received. tion of global photometric parameters, is covered in ° 6. A This paper provides, in some cases for the Ðrst time, stan- detailed discussion of each galaxy, including an analysis of dard global photometric parameters for 14 of the 16 known the surface photometry, is presented in ° 7. Other extended or suspected members of the IC 342/Ma†ei Group, to set sources in the vicinity of the galaxies are described in ° 8. the stage for determining an accurate distance to the group Finally, a brief summary is presented in ° 9. and to evaluate its possible inÑuence on the Local Group in the past. The photometry we present is based on CCD 2. BACKGROUND imaging surveys carried out with the 0.6/0.9 m Burrell- Schmidt Telescope of Kitt Peak National Observatory in 2.1. Census 1992 and 1995. In two previous papers (McCall & Buta The IC 342/Ma†ei Group is located near the northern 1995, 1997), we presented preliminary information on three intersection of the Galactic and supergalactic planes in new probable members of the group identiÐed on our the Galactic coordinate range 129¡ ¹ l ¹ 149¡, survey images. This paper presents our Ðnal results for these [1¡ ¹ b ¹ 16¡. The current census stands at 16 known or galaxies and 11 others, encompassing morphologies, total suspected members, most of which are late-type dwarfs (see magnitudes and color indices, surface brightness proÐles, Krismer, Tully, & Gioia 1995). Table 1 gives the dates of discovery, morphologies (from this paper), heliocentric 1 Visiting Astronomer, Kitt Peak National Observatory, National radial velocities, and positions. In this table, the galaxies are Optical Astronomy Observatories, which is operated by the Association of listed in order of right ascension, but in subsequent tables Universities for Research in Astronomy, Inc., under cooperative agreement and Ðgures they will be listed in alphabetical order to ease with the National Science Foundation. Observations made with the Burrell Schmidt of the Warner and Swasey Observatory, Case Western Ðnding. Figure 1 displays the locations of the galaxies in Reserve University. Galactic coordinates (see also Fig. 1 of Krismer et al. 1995 2 Please direct all correspondence to: Marshall McCall. and of Karachentsev et al. 1997). The group extends 33 34 BUTA & MCCALL Vol. 124 TABLE 1 KNOWN AND SUSPECTED MEMBERS OF THE IC 342/MAFFEI GROUP v_ l bLB Object Discovery Type (km s~1) R.A. (1950) Decl. (1950) (deg) (deg) (deg) (deg) References (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) Cassiopeia 1 ............. 1995 IAB(s)m ]35 02 02 05.0 ]68 46 18.0 129.57 ]7.11 6.28 ]8.48 D1,V1,C1 MB1..................... 1995 IBm ]189 02 31 52.1 ]59 09 39.7 135.85 [0.85 358.98 ]1.41 D2,V2,C2 Maffei 1 .................. 1968 E3 [87 02 32 50.7 ]59 26 16.4 135.86 [0.55 359.29 ]1.44 D3,V3,C2 MB2..................... 1995 I? ? 02 33 16.1 ]59 01 12.8 136.07 [0.91 358.95 ]1.19 D2,V4,C2 Maffei 2 .................. 1968 SAB(rs)bc [23 02 38 08.0 ]59 23 24.0 136.50 [0.33 359.58 ]0.83 D3,V5,C3 Dwingeloo 2 ............. 1995 Im ]91 02 50 19.1 ]58 48 07.0 138.16 [0.19 359.90 [0.81 D4,V6,C4 MB3..................... 1997 dSph ? 02 51 53.2 ]58 39 30.0 138.41 [0.23 359.89 [1.06 D5,V4,C4 Dwingeloo 1 ............. 1994 SB(s)cd ]108 02 53 01.9 ]58 42 38.0 138.52 [0.11 0.02 [1.15 D6,V6,C4 IC342.................... 1895 SA(s)cd ]25 03 41 58.6 ]67 56 26.0 138.17 ]10.58 10.60 ]0.37 D7,V7,C3 UGCA 86................ 1974 SAB(s)m ]80 03 54 59.2 ]66 59 56.6 139.76 ]10.65 10.85 [1.17 D8,V8,C5 Camelopardalis Aa ...... 1994 I/dSph ? 04 19 26.7 ]72 41 27.0 137.25 ]16.20 16.09 ]1.87 D9,V4,C6 NGC 1569 ............... 1789 I (Amorphous) [77 04 26 05.8 ]64 44 18.0 143.68 ]11.24 11.91 [4.92 D10,V9,C3 NGC 1560 ............... 1885 Sd [36 04 27 08.2 ]71 46 29.0 138.37 ]16.02 16.03 ]0.79 D11,V10,C3 UGCA 92................ 1974 IBm [95 04 27 25.9 ]63 30 22.4 144.71 ]10.51 11.32 [6.01 D8,V8,C5 Camelopardalis Ba ...... 1997 I ]75 04 48 03.3 ]67 01 02.0 143.38 ]14.42 15.04 [4.21 D12,V11,C7 UGCA 105 .............. 1974 SAB(s)m ]113 05 09 35.2 ]62 31 19.6 148.52 ]13.66 14.99 [9.25 D8,V8,C5 NOTES.ÈCol. (1): Name of galaxy, in order of right ascension. Col. (2): Date of publication of discovery. Col. (3): Revised Hubble type, based upon images presented in this paper where available. For Cam A and Cam B, types are based upon the judgment of the authors on the basis of published data (see text). Col. (4): Heliocentric radial velocity, in km s~1. Col. (5): Right ascension, epoch 1950, in units of hours, minutes, and seconds. Col. (6): Declination, epoch 1950, in units of degrees, arcminutes, and arcseconds. Col. (7): Galactic longitude. Col. (8): Galactic latitude. Col. (9): supergalactic longitude. Col. (10): supergalactic latitude. Col. (11): References to discovery, velocity, and coordinates. a Not observed for this paper. REFERENCES.ÈDiscovery: (D1) Weinberger 1995 (but also note Blitz et al. 1982); (D2) McCall & Buta 1995; (D3) Ma†ei 1968; (D4) Verheijen, Burton, & Kraan-Korteweg 1995; (D5) McCall & Buta 1997; (D6) Kraan-Korteweg et al. 1994, and Huchtmeier et al. 1995; (D7) Dreyer 1895, based upon a communication from W. F. Denning; (D8) Nilson 1974; (D9) Karachentsev 1994; (D10) Herschel 1789; (D11) Tempel 1885; (D12) Huchtmeier et al.
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