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מאמרים קשורים
Identification of moving groups and member selection using HIPPARCOS data
A new method to identify coherent structures in velocity space - movinggroups - in astrometric catalogues is presented: the Spaghetti method.It relies on positions, parallaxes and proper motions, and is ideallysuited to searching for moving groups in the Hipparcos Catalogue. Noradial-velocity information is required. The method has been testedextensively on synthetic data, and applied to the Hipparcos measurementsfor the Hyades and IC 2602 open clusters. The resulting lists of membersagree very well with those of Perryman et al. for the Hyades and thoseof Whiteoak & Braes for IC 2602.
| An X-ray study of the young open cluster IC 2602.
We present the results of ROSAT PSPC observations of the 30Myr old IC2602 cluster; for the X-ray detected objects the results of a CCDphotometric survey are also given. In X-rays, we detect a total of 110objects within a 11deg^2^ area, above a threshold of typically3-5x10^28^erg/sec. 68 of the detected objects have been identified withat least one optical counterpart; 44 of these are new optical candidatesfor cluster membership provided by our CCD photometry. Stars of allspectral types have been detected, from the very early- types to thelate-M dwarfs. Soft X-ray luminosities range between about 10^29^erg/secto a few 10^30^erg/sec, with the maximum and average L_X_ decreasingwith spectral type for B-V larger than ~0.8. Many of the stars redderthan B-V~0.8 show a L_X_/L_bol_ ratio at about the saturation level of10^-3^. We construct X-ray luminosity distribution functions for objectsin different color ranges and we compare them with those for thePleiades. F, G, and early-K type candidates in IC 2602 appear to be moreX-ray luminous than in the Pleiades, while no significant difference isseen among late-K and M dwarfs. Under the assumption that our IC 2602sample is not severely affected by incompleteness, we argue that theabove finding is related to the distribution of rotational velocities inthe two clusters, with most of the late-type stars being fast rotatorsin both clusters, while, due to different spin-down timescales, theearlier type stars in IC 2602 are likely to rotate more rapidly thantheir counterparts in the Pleiades.
| The Henry Draper Extension Charts: A catalogue of accurate positions, proper motions, magnitudes and spectral types of 86933 stars
The Henry Draper Extension Charts (HDEC), published in the form offinding charts, provide spectral classification for some 87000 starsmostly between 10th and 11th magnitude. This data, being highlyvaluable, as yet was practically unusable for modern computer-basedastronomy. An earlier pilot project (Roeser et al. 1991) demonstrated apossibility to convert this into a star catalogue, using measurements ofcartesian coordinates of stars on the charts and positions of theAstrographic Catalogue (AC) for subsequent identification. We presenthere a final HDEC catalogue comprising accurate positions, propermotions, magnitudes and spectral classes for 86933 stars of the HenryDraper Extension Charts.
| Walraven photometry of nearby southern OB associations
Homogeneous Walraven (VBLUW) photometry is presented for 5260 stars inthe regions of five nearby southern OB associations: Scorpio Centaurus(Sco OB2), Orion OB1, Canis Major OB1, Monoceros OB1, and Scutum OB2.Derived V and (B - V) in the Johnson system are included.
| NGC 2516 and the Pleiades Group
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972ApJ...173...63E&db_key=AST
| K-Line Photometry of Stars in Population i Clusters
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971ApJS...23..453H&db_key=AST
| Photometric studies of southern galactic clusters. II. IC 2602.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74.1011H&db_key=AST
| The galactic cluster IC 2602 (Errata: 17 310)
Not Available
| A study of the galactic cluster IC 2602. I. A photoelectric and spectroscopic investigation
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961MNRAS.123..245W&db_key=AST
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משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | שדרית |
| התרוממות ימנית: | 10h34m58.84s |
| סירוב: | -64°07'43.5" |
| גודל גלוי: | 8.343 |
| מרחק: | 115.875 פארסק |
| תנועה נכונה: | -17.7 |
| תנועה נכונה: | 6.7 |
| B-T magnitude: | 8.503 |
| V-T magnitude: | 8.357 |
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