10 An A3 II (Bresolin et al. 2007ApJ...671.2028B's C3) is located 6.2" away
10 from one association member.
16 Part of the association shows radial distribution around one red and two
16 blue central stars that were not included in the OB catalogue because of
16 their photometric errors.
21 The brightest blue star is a B1 Ia whose spectrum displays strong H{alpha}
21 wind emission (Bresolin et al. 2007ApJ...671.2028B, id: C6).
27 and 28: Their members are horizontally aligned in our images (they have very
27 similar RA), perpendicularly to a spike caused by a nearby saturating
27 bright star. The brightest stars of both associations fall on the spike,
27 and we discard them because their photometry may be altered.
28 and 27: Their members are horizontally aligned in our images (they have very
28 similar RA), perpendicularly to a spike caused by a nearby saturating
28 bright star. The brightest stars of both associations fall on the spike,
28 and we discard them because their photometry may be altered.
43 The brightest star is Bresolin et al. (2007ApJ...671.2028B)'s B11,
43 an O9.5 I.
48 Blue stars 7" away in the SE direction could link this association with #51.
53 Bresolin et al. (2007ApJ...671.2028B)'s C16, an A5 Ib, is included as a red
53 member.
54 A bright blue nearby (8" away) star is missed for the association.
61 Its brightest member is Bresolin et al. (2007ApJ...671.2028B)'s B8 (B8 Ib).
69 The brightest star is Bresolin et al. (2007ApJ...671.2028B)'s B10 (B8 Iab).
75 includes an A5 II (Bresolin et al. 2007ApJ...671.2028B's A2). A nearby red
75 star (not listed as part of the association) could be a red supergiant
75 (RSG).
83 's brightest blue member has very blue Q. It is a Be star (Bresolin et al.
83 2007ApJ...671.2028B's B19); its emission lines may explain its bluer
83 color. Additional faint blue stars are found nearby (at ~7-9").
85 An additional blue star is 7" away.
86 Its brightest member looks triple in the WFPC2 images. A nearby bright red
86 star could be an RSG star of this association.
96 Bresolin et al. (2007ApJ...671.2028B)'s A3 (A7-F0 Ib) is 7" away.
97 Bresolin et al. (2007ApJ...671.2028B)'s A4 (B9 II) is 9" away.
98 An additional blue target 9" away is missed for the association.
99 A member with very blue Q has the same position in the U-B vs. Q diagram as
99 IC 1613's WO. However, this object may be blended with the brightest
99 association member.
103 Bresolin et al. (2007ApJ...671.2028B)'s A4 star, a B9 II, is included in the
103 association. Because of its late spectral type, this object's Q color is
103 slightly beyond our Q constraint for blue stars (i.e., Q>-0.4).
104 contains Bresolin et al. (2007ApJ...671.2028B)'s C17 star, an early-A II.
104 The target enters the catalogue as a red star (Q >-0.4).
105 contains Bresolin et al. (2007ApJ...671.2028B)'s A5 star (B3 Ib). (This
105 association was discarded because it only has 2 valid members).
106 The brightest star is Bresolin et al. (2007ApJ...671.2028B)'s A4b star
106 (B5 Ib).
114 is a round association located at the outer part of the galaxy. The
114 brightest blue star (V~18.5) could be blended with the next two brightest
114 stars of the association, although the targets are well resolved in
114 VLT-VIMOS images.
116 A B0 Iab star (Bresolin et al. 2007ApJ...671.2028B's B14) is close to the
116 association.
117 The position of the red member in the color-magnitude diagrams matches that
117 of an RSG. Close to association #114, together they could form a ring.
120 The brightest member is Bresolin et al. (2007ApJ...671.2028B)'s A7, B2 Iab.
122 The brightest blue member is Bresolin et al. (2007ApJ...671.2028B)'s B16,
122 B1.5 Iab.
124 's brightest member is an A0 III (Bresolin et al. (2007ApJ...671.2028B),
124 id: B15).
125 Its brightest member could be contaminated by a nearby red star, although
125 its normal colors suggest otherwise.
126 The brightest star has very blue Q and its colors deviate from the reddening
126 law, but visual inspection reveals that it is a normal isolated star. This
126 star is [AM85] 3, with spectral type OB+em (Azzopardi et al.
126 1988A&A...189...34A). The nebular emission could explain its anomalously
126 blue Q.
127 delineates the bright part of one of the bubbles of the NE lobe. #127 may
127 form a single giant asisociation with #147. Spectral types are known for
127 three stars in the association: the brightest blue stars have types A2 Ia
127 and B1.5 Ia (Bresolin et al. (2007ApJ...671.2028B)'s id's are A8 and B4).
127 Skiff (2007, Cat. ) assigns A0 Ia(e) to the former and additionally
127 lists an RSG, [S71] V32 with type M1 Ia (not included in our catalogue
127 because of the hard constraints on blue photometric errors). The
127 A-supergiant has been suggested to be a foreground star (Sandage & Katem
127 1976AJ.....81..743S), but Bresolin et al. (2007ApJ...671.2028B) found its
127 radial velocity to be in agreement with IC 1613, and report P Cygni
127 profiles of H{gamma} and H{beta} (see Sect. 5.1.1).
127 Spectroscopy of higher resolution than Bresolin et al.
127 (2007ApJ...671.2028B)'s VLT-FORS2 data is needed to determine whether this
127 object is an LBV-candidate.
128 The brightest star is a Be (Bresolin et al. 2007ApJ...671.2028B's B5), and
128 this may explain its very blue Q color.
134 A possible additional member, bright and blue, is 7" away.
136 marks a bubble rim.
137 is formed by several arc-like structures that possibly trace the edges of
137 several bubbles. Four members to the west could form a separate
137 association. The brightest member is a B supergiant: B1 Ia (Bresolin et al.
137 2007ApJ...671.2028B's A10), B2/3 Ie (Skiff 2007, Cat. ), B2-3 I
137 (Humphreys 1980ApJ...238...65H). The second brightest star is
137 Bresolin et al. (2007ApJ...671.2028B)'s A9 (B5 Iab).
140 A nearby blue star (~7" away) is not included in the association.
144 The brightest member ionizes its surrounding nebula.
146 The brightest member is a Be (Bresolin et al. 2007ApJ...671.2028B, id: B12).
147 is dominated by 2 clumps, each in the intersection of 2 bubbles, plus 2
147 arc-like structures that trace the rim of one bubble each. Some detections
147 are actually nebular knots (discarded). The association has 5 bright
147 members (V in [19,20]), four of them in the largest clump of stars.
147 Lozinskaya et al. (2003AstL...29...77L) obtained low resolution spectra
147 (Delta{lambda=8{AA}) of the stars in the main clump, with a 6m telescope
147 (note that this area is barely resolved, even in the VLT-VIMOS images). The
147 group includes an Of star, two O giants and two OB candidates. The
147 association has an additional OB member, far from the regions of crowding
147 (OB+em?, Azzopardi et al. 1988A&A...189...34A).
148 A nearby blue star, a potential member of the association, is 7.5" away.
149 is in the bubble region, between the large associations #137 and #147, but
149 no nebulosity is seen nearby.
151 is the association with more OB members of our catalogue. It is arc-shaped
151 and part of it follows one bubble. IC 1613's known supernova remnant (SNR)
151 is included in the association. Our catalogue yields 5 detections for the
151 SNR, which we discard. We note here one apparently isolated target whose
151 position in the Q vs. U-B and B-V vs. U-B color-color diagrams is the same
151 as for the WO star. Several obscured clouds fall within the limits of the
151 association. The age of the SNR is yet undecided since it shows both young
151 and old signatures. While it was originally believed to be about 2x10^4^
151 years old (Dodorico & Dopita 1983, Supernova Remnants and their X-ray
151 Emission, 101, 517; Peimbert et al. 1988RMxAA..16...45P) X-ray observations
151 suggest an age of 3x10^3^ years (Jones et al. 1998PASP..110..125J). The
151 emission lines from the knots resemble those from the Crab Nebula and
151 Cygnus Loop filaments, indicating that this is a young SNR (Armandroff &
151 Massey 1991AJ....102..927A). It has been suggested that the SN exploded
151 inside a large cavity surrounded by a dense H I cloud. The remnant would
151 have just encountered the dense material, producing shocks and hence the
151 peculiar features (Lozinskaya et al. 2003AstL...29...77L,
151 1998AJ....116.2328L). Spectral types are known for three stars in this
151 association. The two brightest blue stars are an O9 I and a B1 Ia, Bresolin
151 et al. (2007ApJ...671.2028B)'s B7 and B6. The authors report strong $\rm
151 H{alpha} wind emission in the spectrum of B6. The association contains
151 a red supergiant, Sandage & Katem (1976AJ.....81..743S)'s variable star
151 [S71] V38 (M0 Ia, Skiff 2007, Cat. ). The RSG is only 6.7" away
151 from association #150.
154 encloses IC 1613's known WO star. The object has very blue Q and U-B colors
154 (V=19.86, Q=-1.35, B-V=0.02, U-B=-1.33). The WO is located on the edge of
154 the giant H I shell that contains the SW side of the galaxy, and ionizes
154 an asymmetric bipolar H II region (Afanas'ev et al. 2000AstL...26..153A;
154 Lozinskaya et al. 2001ARep...45..417L). These authors find at least two
154 extra sources in H{alpha} and HeII 4686 narrow-band filters that are
154 compact knots of gas. Some entries of our OB candidate list are also knots
154 of the nebula ionized by the WR. They are characterized by very blue Q and
154 red B-V. However, U, B and R VLT-VIMOS images suggest that two of the
154 detections (besides the WO) are in fact stars. One of them has very blue Q,
154 and the other one, very embedded in the WO nebula, has red Q. These stars
154 might be members of a cluster hidden behind the WO, proposed by Lozinskaya
154 et al. (2001ARep...45..417L). The bipolar shell's dynamical age is
154 0.3-1x10^6^ years (Afanas'ev et al. 2000AstL...26..153A), consistent with
154 the duration of the WR stage.
157 VLT-VIMOS images reveal that the brightest star is triple, and unresolved in
157 our catalogue. One member has similar colors to the brightest star in #158,
157 which has been found to be an LBV-candidate.
158 is located in the void of the bubble region, like #149. One of the members
158 has very red B-V and blue Q. Medium resolution spectroscopy soon to be
158 published (Herrero et al. 2009, in prep.) has revealed P Cygni profiles of
158 the Balmer series and of iron, rendering the target an LBV-candidate.
161 traces two bubble rims, sharing one of them with association #147. The
161 brightest target is Bresolin et al. (2007ApJ...671.2028B)'s A11 (B9 Ia).
162 's brightest star is in the intersection with one of the bubble rims
162 followed by #161. Its spectral type is O5-O6 V (Bresolin et al.
162 2007ApJ...671.2028B's B2), and it is likely ionizing its surrounding
162 nebula.
175 The association is spatially divided into two parts, one at the centre of a
175 bubble, and the other in the intersection of such bubble and another that
175 encloses association #185. One apparently isolated member has very blue Q
175 (~-1.4), and its position in the Q vs. U-B and B-V vs. U-B diagrams is
175 similar to the WO.
176 Two out of its three members are in the centre of a small bubble.
179 's brightest star is Bresolin et al. (2007ApJ...671.2028B)'s A12,
179 a B1.5 Iab.
184 is found in the SW outskirts of the galaxy. The stars are distributed in a
184 ring shape, around a central red star.
185 Members are located on the rim of one bubble, but they may also be creating
185 the bubble where part of association #175 is located at the SW. The
185 association has a high stellar density and all members may experience
185 blends. The brightest star is an early B-supergiant (B0 Ia Bresolin et al.
185 2007ApJ...671.2028B's B3; B:I: Sandage & Katem 1976AJ.....81..743S's B42)
185 although Lozinskaya et al. (2002ARep...46...16L) classified it as an O
185 supergiant. The study of the latter in this region (see comment on
185 association #147 for a description of their analysis) found 3 more OB
185 stars: O III, B8 II and one with uncertain type O8 III or O4 V . A faint
185 member (V~22$) with extremely blue Qand U-B, lies in the same position
185 in the U-B vs. Q diagram as the WO.
187 's brightest member is Bresolin et al. (2007ApJ...671.2028B)'s A13 a very
187 early O dwarf (O3-4 V((f))), which is remarkable for a modest association
187 of only 3 members.
189 is located on the rim of a bubble. The spatial distribution suggests that
189 the H II shell could have been blown away either by association #185 or by
189 a nearby isolated star.
191 is linear in shape and located in the bubble region, close to association
191 #189. The brightest star is a late-O giant (O9 III, Bresolin et al.
191 2007ApJ...671.2028B's A15).
196 's brightest star is a Be, Bresolin et al. (2007ApJ...671.2028B)'s A17.
196 Their target A16 (early-B Ib) is only 6.1" away.