2004A&A...420..605M


C.D.S. - SIMBAD4 rel 1.7 - 2021.03.02CET06:13:56

2004A&A...420..605M - Astronomy and Astrophysics, volume 420, 605-617 (2004/6-3)

The ubiquitous nature of the horizontal branch second U-jump. A link with the Blue Hook scenario?

MOMANY Y., BEDIN L.R., CASSISI S., PIOTTO G., ORTOLANI S., RECIO-BLANCO A., DE ANGELI F. and CASTELLI F.

Abstract (from CDS):

In a previous paper we reported on a discontinuity in the extreme horizontal branch (EHB) of the Galactic globular cluster NGC 6752, which we called the second U-jump. This feature was attributed to a combination of post zero-age horizontal branch evolution and diffusion effects. In this follow-up study we analyze other EHB clusters and show that the second U-jump is a common feature among EHB clusters reaching Teff≥23000K, and that its onset in different clusters converges around Teff∼21000±3000K. We also present near-ultraviolet diagrams of ωCen and NGC 2808, the only two objects with spectroscopically confirmed ``blue hook'' stars (Teff≥35000K). We confirm predictions of a photometric discontinuity separating late from early-helium flashers. Moreover, we present empirical evidence that the second U-jump population might be mainly composed of early-helium flashers. Lastly, we revisit the discussion on the ubiquitous nature of the gaps and jumps so far identified in the blue HB tails, suggesting a possible discrete nature of the distribution in temperature of the HB stars.

Abstract Copyright:

Journal keyword(s): stars: horizontal-branch - stars: Hertzsprung-Russell (HR) and C-M diagrams - stars: Population II - Galaxy: globular clusters: general - ultraviolet: stars

Simbad objects: 24

goto Full paper

goto View the reference in ADS

Number of rows : 24

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 NGC 288 GlC 00 52 45.24 -26 34 57.4   10 8.13     ~ 942 0
2 M 79 GlC 05 24 10.59 -24 31 27.3   9.21 8.16     ~ 730 0
3 NGC 2808 GlC 09 12 03.10 -64 51 48.6   7.77 5.69     ~ 1277 0
4 [MSL2002] J132553.96-473521.3 HB* 13 25 03.96 -47 35 21.3     18.891     ~ 3 0
5 [MSL2002] J132514.72-473236.0 HB* 13 25 14.8179333918 -47 32 35.694071207     18.867     ~ 4 0
6 [MDL2011] 24609 HB* 13 25 34.2678879768 -47 29 50.148586176   18.708 18.921     ~ 5 0
7 [MSL2002] J132535.57-472745.1 HB* 13 25 35.5545034026 -47 27 45.468786550   18.836 19.103     ~ 4 0
8 Cl* NGC 5139 BPB 184717 HB* 13 25 41.3 -47 29 06 17.539 18.803 18.900   19.186 ~ 6 0
9 [MSL2002] J132546.54-472651.7 HB* 13 25 46.54 -47 26 51.7     19.220     ~ 3 0
10 Cl* NGC 5139 BPB 123934 HB* 13 25 50.1360743976 -47 32 06.394948193 17.241 18.521 18.547   18.807 ~ 6 0
11 [MDL2011] 65373 HB* 13 26 08.8261139362 -47 37 12.544370625 16.941 18.355 18.556   18.749 ~ 6 0
12 [MSL2002] J132624.95-473323.2 HB* 13 26 24.930 -47 33 23.54 17.035 18.322 18.418   18.489 ~ 4 0
13 [MSL2002] J132633.23-473512.3 HB* 13 26 33.213 -47 35 12.60 16.937 18.351 18.548   18.826 ~ 4 0
14 NGC 5139 GlC 13 26 47.28 -47 28 46.1   6.12 5.33     ~ 3072 0
15 [MSL2002] J132725.95-473219.6 HB* 13 27 25.943 -47 32 19.69 16.503 17.812 17.959   18.133 ~ 4 0
16 NGC 5986 GlC 15 46 03.00 -37 47 11.1     6.92     ~ 317 0
17 M 80 GlC 16 17 02.41 -22 58 33.9           ~ 637 0
18 M 13 GlC 16 41 41.634 +36 27 40.75     5.8     ~ 2036 0
19 M 19 GlC 17 02 37.69 -26 16 04.6   8.45 5.57     ~ 318 1
20 M 22 GlC 18 36 23.94 -23 54 17.1   7.16 6.17     ~ 1242 0
21 M 54 GlC 18 55 03.33 -30 28 47.5           ~ 932 0
22 NGC 6752 GlC 19 10 52.11 -59 59 04.4   6.96 6.28     ~ 1835 0
23 M 2 GlC 21 33 27.02 -00 49 23.7     6.25     ~ 920 1
24 M 30 GlC 21 40 22.12 -23 10 47.5     7.10     ~ 940 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2004A&A...420..605M and select 'bookmark this link' or equivalent in the popup menu


2021.03.02-06:13:56

© Université de Strasbourg/CNRS

    • Contact