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HR 7355 - another rapidly braking He-strong CP star?
Context. Strong meridional mixing induced by rapid rotation is onereason why all hot main-sequence stars are not chemically peculiar.However, the finding that the He-strong CP star HR 7355 is a rapidrotator complicates this concept. Aims: Our goal is to explainthe observed behaviour of HR 7355 based on period analysis of allavailable photometry. Methods: Over two years, we acquired 114new BV observations of HR 7355 at observatories inArizona, U.S.A and Cape Town, South Africa. We performed period analysesof the new observations along with new analyses of 732 archivalmeasurements from the Hipparcos and ASAS projects. Results: Wefind that the light curves of HR 7355gt; in variousfilters are quite similar, with amplitudes 0.035(4), 0.036(4), and0.038(3) mag in B, Hp, and V, respectively. The light curves aredouble-peaked, with unevenly deep minima. We substantially refine therotational period to be P = 0.5214410(4)d, indicating that HR7355gt; is the most rapidly rotating CP star known. Our periodanalyses reveal a possible lengthening of the rotational period withdot{P}/P = 2.4(8)×10-6 yr-1. Conclusions: We conclude that the shape and amplitude of HR7355gt; light curves are typical of magnetic He-strong CPstars, for which light variations are the result of photospheric spotson the surface of a rotating star. We hypothesise that the lightvariations are caused mainly by an uneven distribution of overabundanthelium on the star's surface. We briefly describe and discuss the causeof the rapid rotational braking of the star.Photometric data are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/511/L7
| Magnetic fields of chemically peculiar stars. I. The catalog of magnetic CP stars
This is the first paper of the series dedicated to the analysis of themagnetism of chemically peculiar (CP) stars of the upper Main Sequence.We use our own measurements and published data to compile a catalog ofmagnetic CP stars containing a total of 326 objects with confidentlydetected magnetic fields and 29 stars which are very likely to possessmagnetic field. We obtained the data on the magnetism of theoverwhelming majority of the stars solely based on the analysis oflongitudinal field component B e . The surface magneticfield, B s , has been measured for 49 objects. Our analysisshows that the number of magnetic CP stars decreases with increasingfield strength in accordance with exponential law, and stars with B e exceeding 5kG occur rarely (about 3% objects of ourlist).
| Searching for links between magnetic fields and stellar evolution: II. The evolution of magnetic fields as revealed by observations of Ap stars in open clusters and associations
Context: The evolution of magnetic fields in Ap stars during the mainsequence phase is presently mostly unconstrained by observation becauseof the difficulty of assigning accurate ages to known field Ap stars. Aims: We are carrying out a large survey of magnetic fields in clusterAp stars with the goal of obtaining a sample of these stars withwell-determined ages. In this paper we analyse the information availablefrom the survey as it currently stands. Methods: We select from theavailable observational sample the stars that are probably (1) clusteror association members and (2) magnetic Ap stars. For the stars in thissubsample we determine the fundamental parameters T{eff},L/L_ȯ, and M/M_ȯ. With these data and the cluster ages weassign both absolute age and fractional age (the fraction of the mainsequence lifetime completed). For this purpose we have derived newbolometric corrections for Ap stars. Results: Magnetic fields arepresent at the surfaces of Ap stars from the ZAMS to the TAMS.Statistically for the stars with M > 3 M_ȯ the fields declinewith advancing age approximately as expected from flux conservationtogether with increased stellar radius, or perhaps even faster than thisrate, on a time scale of about 3×107 yr. In contrast,lower mass stars show no compelling evidence for field decrease even ona timescale of several times 108 yr. Conclusions: Study ofmagnetic cluster stars is now a powerful tool for obtaining constraintson evolution of Ap stars through the main sequence. Enlarging the sampleof known cluster magnetic stars, and obtaining more precise rms fields,will help to clarify the results obtained so far. Further fieldobservations are in progress.Tables 2 and 3 are only available in electronic form athttp://www.aanda.org
| Evolution of magnetic fields in stars across the upper main sequence: II. Observed distribution of the magnetic field geometry
We re-discuss the evolutionary state of upper main sequence magneticstars using a sample of Ap and Bp stars with accurate Hipparcosparallaxes and definitely determined longitudinal magnetic fields. Weconfirm our previous results obtained from the study of Ap and Bp starswith accurate measurements of the mean magnetic field modulus and meanquadratic magnetic fields that magnetic stars of mass {M}<3 M_ȯare concentrated towards the centre of the main-sequence band. Incontrast, stars with masses {M}>3 M_ȯ seem to be concentratedcloser to the ZAMS. The study of a few known members of nearby openclusters with accurate Hipparcos parallaxes confirms these conclusions.Stronger magnetic fields tend to be found in hotter, younger and moremassive stars, as well as in stars with shorter rotation periods. Thelongest rotation periods are found only in stars which spent alreadymore than 40% of their main sequence life, in the mass domain between1.8 and 3 M_ȯ and with log g values ranging from 3.80 to 4.13. Noevidence is found for any loss of angular momentum during themain-sequence life. The magnetic flux remains constant over the stellarlife time on the main sequence. An excess of stars with largeobliquities β is detected in both higher and lower mass stars. It isquite possible that the angle β becomes close to 0o inslower rotating stars of mass {M}>3 M_ȯ too, analog to thebehaviour of angles β in slowly rotating stars of {M}<3 M_ȯ.The obliquity angle distribution as inferred from the distribution ofr-values appears random at the time magnetic stars become observable onthe H-R diagram. After quite a short time spent on the main sequence,the obliquity angle β tends to reach values close to either90o or 0o for {M}<3 M_ȯ. The evolution ofthe obliquity angle β seems to be somewhat different for low andhigh mass stars. While we find a strong hint for an increase of βwith the elapsed time on the main sequence for stars with {M}>3M_ȯ, no similar trend is found for stars with {M}<3 M_ȯ.However, the predominance of high values of β at advanced ages inthese stars is notable. As the physics governing the processes takingplace in magnetised atmospheres remains poorly understood, magneticfield properties have to be considered in the framework of dynamo orfossil field theories.
| Evolution of magnetic fields in stars across the upper main sequence: I. Catalogue of magnetic field measurements with FORS 1 at the VLT
To properly understand the physics of Ap and Bp stars it is particularlyimportant to identify the origin of their magnetic fields. For that, anaccurate knowledge of the evolutionary state of stars that have ameasured magnetic field is an important diagnostic. Previous resultsbased on a small and possibly biased sample suggest that thedistribution of magnetic stars with mass below 3 M_ȯ in the H-Rdiagram differs from that of normal stars in the same mass range (Hubriget al. 2000). In contrast, higher mass magnetic Bp stars may well occupythe whole main-sequence width (Hubrig, Schöller & North 2005b).In order to rediscuss the evolutionary state of upper main sequencemagnetic stars, we define a larger and bias-free sample of Ap and Bpstars with accurate Hipparcos parallaxes and reliably determinedlongitudinal magnetic fields. We used FORS 1 at the VLT in itsspectropolarimetric mode to measure the magnetic field in chemicallypeculiar stars where it was unknown or poorly known as yet. In thisfirst paper we present our results of the mean longitudinal magneticfield measurements in 136 stars. Our sample consists of 105 Ap and Bpstars, two PGa stars, 17 HgMn stars, three normal stars, and nine SPBstars. A magnetic field was for the first time detected in 57 Ap and Bpstars, in four HgMn stars, one PGa star, one normal B-type star and fourSPB stars.
| Searching for links between magnetic fields and stellar evolution. I. A survey of magnetic fields in open cluster A- and B-type stars with FORS1
Context: .About 5% of upper main sequence stars are permeated by astrong magnetic field, the origin of which is still matter of debate. Aims: . With this work we provide observational material to studyhow magnetic fields change with the evolution of stars on the mainsequence, and to constrain theory explaining the presence of magneticfields in A and B-type stars. Methods: . Using FORS1 inspectropolarimetric mode at the ESO VLT, we have carried out a survey ofmagnetic fields in early-type stars belonging to open clusters andassociations of various ages. Results: . We have measured themagnetic field of 235 early-type stars with a typical uncertainty of 100 G. In our sample, 97 stars are Ap or Bp stars. For thesetargets, the median error bar of our field measurements was 80 G.A field has been detected in about 41 of these stars, 37 of which werenot previously known as magnetic stars. For the 138 normal A and B-typestars, the median error bar was 136 G, and no field was detected in anyof them.
| Evolutionary state of magnetic chemically peculiar stars
Context: .The photospheres of about 5-10% of the upper main sequencestars exhibit remarkable chemical anomalies. Many of these chemicallypeculiar (CP) stars have a global magnetic field, the origin of which isstill a matter of debate. Aims: .We present a comprehensivestatistical investigation of the evolution of magnetic CP stars, aimedat providing constraints to the theories that deal with the origin ofthe magnetic field in these stars. Methods: .We have collectedfrom the literature data for 150 magnetic CP stars with accurateHipparcos parallaxes. We have retrieved from the ESO archive 142 FORS1observations of circularly polarized spectra for 100 stars. From thesespectra we have measured the mean longitudinal magnetic field, anddiscovered 48 new magnetic CP stars (five of which belonging to the rareclass of rapidly oscillating Ap stars). We have determined effectivetemperature and luminosity, then mass and position in the H-R diagramfor a final sample of 194 magnetic CP stars. Results: .We foundthat magnetic stars with M > 3 ~M_ȯ are homogeneouslydistributed along the main sequence. Instead, there are statisticalindications that lower mass stars (especially those with M ≤2~M_ȯ) tend to concentrate in the centre of the main sequence band.We show that this inhomogeneous age distribution cannot be attributed tothe effects of random errors and small number statistics. Our datasuggest also that the surface magnetic flux of CP stars increases withstellar age and mass, and correlates with the rotation period. For starswith M > 3~M_ȯ, rotation periods decrease with age in a wayconsistent with the conservation of the angular momentum, while for lessmassive magnetic CP stars an angular momentum loss cannot be ruledout. Conclusions: .The mechanism that originates and sustains themagnetic field in the upper main sequence stars may be different in CPstars of different mass.
| The field of IC 2602: Strömgren-Hβ photometry approach
A homogeneous data-base collating all uvbyβ photometry available atpresent for O-B9 stars in the field of IC 2602 is presented. Thecharacteristics of the field are studied. Four spatially coherent groupscan be distinguished. A low reddened compact group located at156±6 pc is identified with IC 2602, followed by backgroundlayers at 546±33 pc, 1117±61 pc, and possibly at2626±163 pc. The apparent depth of the first three layers isabout 1 kpc, which is consistent with the thickness of a spiral arm.There is an indication for the existence of a region free of massiveluminous stars between 1.2 and 2.6 kpc, which could be associated withinterarm space between the Local Association and the distant spiralstructures toward Carina. A comparison between the photometric andHipparcos parallaxes is presented.
| On the evolutionary status of chemically peculiar stars of the upper main sequence
We present further evidence that the magnetic chemically peculiar stars(CP2) of the upper main sequence already occur at very early stages ofthe stellar evolution, significantly before they reach 30% of theirlife-time on the main sequence. This result is especially important formodels dealing with dynamo theories, angular momentum loss during thepre- as well as main sequence and evolutionary calculations for CP2stars. Results from the literature either derived for objects in theHyades and the UMa cluster or from the Hipparcos mission contradict eachother. A way out of this dilemma is to investigate young open clusterswith known ages and accurate distances (error <10%), including CP2members. Up to now, four open clusters fulfill these requirements: IC2391, IC 2602, NGC 2451 A and NGC 2516. In total, 13 CP2 stars can befound within these clusters. We have used the measurements andcalibrations of the Geneva 7-color photometric system to deriveeffective temperatures and luminosities. Taking into account the overallmetallicity of the individual clusters, isochrones and evolutionarytracks were used to estimate ages and masses for the individual objects.The derived ages (between 10 and 140 Myr) are well in line with those ofthe corresponding clusters and further strengthen the membership of theinvestigated CP2 stars.Based on observations by the Hipparcos satellite.
| Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
| Strömgren and Hβ photometry of O and B type stars in star-forming regions. III. Carina Spiral Feature
Strömgren and Hβ photometry of O and B type stars, generallybrighter than 9.5 mag is reported for the field of the Carina SpiralFeature. The observations are based on the PPM catalogue identificationsand are designed to improve the completeness of the existing uvbybetadata for the bright early-type stars in the field. We present new uvbyphotometry for 283 stars and Hβ photometry for 225 of them. Theseobservations are part of an ongoing effort to study the structure ofselected star-forming regions in the Milky Way by means of uvbybetaphotometry. A comparison of the new data to other uvbybeta data sets forthis field is presented. Based on data from the Strömgren AutomaticTelescope of the Copenhagen University Observatory, La Silla. Tables 1and 2 are only available in electronic form at the CDS via anonymous ftpto 130.79.128.5 or via http://cdsweb.u-strasbg.fr/Abstract.html
| Blue stragglers in open clusters. Part II
We present the results of a spectroscopic study of blue straggler andmain sequence B and A - type stars in the open clusters NGC 3496, NGC6475, NGC 6633 and IC 2602. A detailed analysis based on Kurucz'satmosphere models showed that the main sequence stars rotate ratherrapidly and differ from a normal (solar) metallicity for only a fewlight elements. The blue stragglers have significantly smaller projectedrotational velocities. As a group, they show the same chemicalpeculiarities as ordinary cluster and galactic field stars of the samespectral type. Two blue stragglers and one main sequence star possess arather low helium content. All investigated stars for which the carbonabundance could be measured showed a moderate-to-strong deficiency ofthis element. The phenomenon of the blue stragglers is briefly discussedon the basis of our study. Based on observations collected at EuropeanSouthern Observatory.
| Hβ photometry of southern CP2 stars: is the uvbybeta luminosity calibration also valid for peculiar stars?
We present Hβ photometry of 233 southern CP2 stars (covering themagnetic Ap stars according to the definition by Preston 1974) brighterthan V < 8.5 mag from the list of Bidelman & MacConnell (1973).Absolute magnitudes derived from this photometry together with alreadyexisting uvby photometry is confronted with Hipparcos results availablefor a common subset of 152 stars. In order to compare peculiar withnormal stars, we identified a sample of 1147 normal B to F-type starsusing their published uvbybeta and Hipparcos data. For our analysis wedivide both samples into three temperature as well as two Hipparcosparallax accuracy groups. The error distribution of both samples provedto be statistically comparable. As a result the absolute magnitudes forthe B-type CP2 stars show up to be significantly too bright by anaverage of 0.5 mag using the actual photometric calibration. On theother hand, the photometric absolute magnitudes for cool A to F-type CP2stars are up to three magnitudes fainter as compared to Hipparcos. Basedon observations at ESO-La Silla and with the Hipparcos satellite
| 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.
| Open clusters with Hipparcos. I. Mean astrometric parameters
New memberships, mean parallaxes and proper motions of all 9 openclusters closer than 300 pc (except the Hyades) and 9rich clusters between 300 and 500 pc have been computed using Hipparcosdata. Precisions, ranging from 0.2 to 0.5 mas for parallaxes and 0.1 to0.5 mas/yr for proper motions, are of great interest for calibratingphotometric parallaxes as well as for kinematical studies. Carefulinvestigations of possible biases have been performed and no evidence ofsignificant systematic errors on the mean cluster parallaxes has beenfound. The distances and proper motions of 32 more distant clusters,which may be used statistically, are also indicated. Based onobservations made with the ESA Hipparcos astrometry satellite
| On the HIPPARCOS photometry of chemically peculiar B, A, and F stars
The Hipparcos photometry of the Chemically Peculiar main sequence B, A,and F stars is examined for variability. Some non-magnetic CP stars,Mercury-Manganese and metallic-line stars, which according to canonicalwisdom should not be variable, may be variable and are identified forfurther study. Some potentially important magnetic CP stars are noted.Tables 1, 2, and 3 are available only in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| The HR-diagram from HIPPARCOS data. Absolute magnitudes and kinematics of BP - AP stars
The HR-diagram of about 1000 Bp - Ap stars in the solar neighbourhoodhas been constructed using astrometric data from Hipparcos satellite aswell as photometric and radial velocity data. The LM method\cite{luri95,luri96} allows the use of proper motion and radial velocitydata in addition to the trigonometric parallaxes to obtain luminositycalibrations and improved distances estimates. Six types of Bp - Apstars have been examined: He-rich, He-weak, HgMn, Si, Si+ and SrCrEu.Most Bp - Ap stars lie on the main sequence occupying the whole width ofit (about 2 mag), just like normal stars in the same range of spectraltypes. Their kinematic behaviour is typical of thin disk stars youngerthan about 1 Gyr. A few stars found to be high above the galactic planeor to have a high velocity are briefly discussed. Based on data from theESA Hipparcos astrometry satellite and photometric data collected in theGeneva system at ESO, La Silla (Chile) and at Jungfraujoch andGornergrat Observatories (Switzerland). Tables 3 and 4 are onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| The observed periods of AP and BP stars
A catalogue of all the periods up to now proposed for the variations ofCP2, CP3, and CP4 stars is presented. The main identifiers (HD and HR),the proper name, the variable-star name, and the spectral type andpeculiarity are given for each star as far as the coordinates at 2000.0and the visual magnitude. The nature of the observed variations (light,spectrum, magnetic field, etc.) is presented in a codified way. Thecatalogue is arranged in three tables: the bulk of the data, i.e. thosereferring to CP2, CP3, and CP4 stars, are given in Table 1, while thedata concerning He-strong stars are given in Table 2 and those foreclipsing or ellipsoidal variables are collected in Table 3. Notes arealso provided at the end of each table, mainly about duplicities. Thecatalogue contains data on 364 CP stars and is updated to 1996, October31. This research has made use of the SIMBAD database, operated at CDS,Strasbourg, France.
| 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.
| Period of the Si-star in NGC 2169
For the Si Ap-star known in NGC 2169 (Gr.9 in the cluster), a periodbetween 0.60 and 0.62 d, most likely about 0.606 d, agrees with allknown observations, and is much more probable than the period 1.56 dproposed by Maitzen & Lebzelter (1993). The obtained period is amongthe shortest ones known for Ap stars.
| A new list of effective temperatures of chemically peculiar stars. II.
Not Available
| Liste des étoiles Ap et Am dans les amas ouverts (édition révisée)
Not Available
| Liste des étoiles Ap et Am dans les amas ouverts (Edition révisée)
Not Available
| 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.
| Radii and space orientation of the rotational axes of AP stars
The inclination of the rotation axis to the line of sight (i) has beendetermined for a carefully selected sample of Ap stars with reliablevalues of periods of rotation, and values of the stellar radius (R)times sin i have been compared with values of normal main-sequencestars. The findings that none of the obtained R x sin i values aresignificantly larger than the upper limit for the radius of a mainsequence stars and that the mean radius of Ap stars is close to thenormal main sequence value suggest that most Ap stars are main-sequenceobjects. The observed i distribution implies that the distribution ofthe rotational axes of Ap stars in space is random.
| Catalog of AP and AM stars in open clusters
The previous results of Raab (1922), Markarian (1951), and Collinder(1931) have been used to catalog Ap and Am stars that are in the fieldof open clusters. Tabular data are presented for the clusterdesignation, the HD or HDE number, the right ascension (1900), thedeclination (1900), and the magnitude. Also listed are the spectraltypes and, for certain stars, the probability of cluster membership.
| Photoelectric search for CP2-stars in open clusters. XIII - NGC 3114 and IC 2602
Delta-a photometric observations of two open clusters, obtained usingthe 50-cm and 1-m telescopes at ESO during 1981-1984, are reported. Thedata are presented in extensive tables and graphs and brieflycharacterized. Of the 168 stars measured, eight (six in NGC 3114 and twoin IC 2602) are identified as chemically peculiar upper-main-sequenceobjects with magnetic fields. These hot CP2 stars are found to beblueshifted relative to the cluster main sequences on the V/(b-y)diagrams.
| Starbursts, binary stars, and blue stragglers in local superclusters and groups. I - The very young disk and young disk populations
The distributions in the HR diagram with theoretical time-constant locifor stars in several young clusters and superclusters are compared todemonstrate that 'blue stragglers' in these aggregates are mostfrequently simply single massive (mode B) stars formed in bursts of starformation that occur at discrete intervals in time following theformation of the bulk of the low-mass (mode A) stars in the aggregate.The characteristics of the close binary systems in these aggregates areexamined to show that, in several cases, mass transfer by Roche lobeoverflow has or will occur and that, in some instances, the system wouldhave appeared as a blue straggler prior to the mass-transfer event, and,in other instances, mass transfer will lead to the identification of thesystem as a blue straggler. Thus, it is concluded that the bluestraggler phenomenon has at least two distinct physical origins: it mayoriginate from delayed formation (starbursts) or from 'delayedevolution' in some close binaries (mass transfer from an evolvedprimary).
| First supplement to the catalog of observed periods of AP stars
Supplementary data on the periods of Ap stars with references arepresented; 58 new stars are introduced for which periodic variabilityhas been discovered since 1983. For some of these stars periodicity wasknown before 1983 but they were not reported in the previous catalog.Recently attributed variable star names are also reported.
| Chemically peculiar stars in open clusters. I - The catalog
The largest existing compilation is presented of Ap and Am open clusterstars. The catalog contains information on 381 chemically peculiar (CP)stars of the upper main sequence in 79 open clusters. The catalog iscomposed of the following tables: (1) the main body, which lists CP (orsuspected CP) stars which are kinematical (or suspected kinematical)members of open clusters; (2) the list of CP (or suspected CP) starssometimes numbered among cluster members but which are actuallykinematical nonmembers; (3) the list of stars sometimes designated as'peculiar' but, in fact, probably not CP; (4) references for numberingsystems of cluster stars; (5) references for membership; and (6)references for spectral and/or peculiarity types.
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לינקים קשורים
הכנס לינק חדש
משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | שדרית |
| התרוממות ימנית: | 10h38m17.55s |
| סירוב: | -65°02'31.0" |
| גודל גלוי: | 6.706 |
| מרחק: | 147.493 פארסק |
| תנועה נכונה: | -17.1 |
| תנועה נכונה: | 10.1 |
| B-T magnitude: | 6.632 |
| V-T magnitude: | 6.7 |
קטלוגים וכינוים:
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