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|Shocked Clouds in the Vela Supernova Remnant|
Unusually strong high-excitation C I has been detected in 11 lines ofsight through the Vela supernova remnant (SNR) by means of UV absorptionline studies of IUE data. Most of these lines of sight lie near thewestern edge of the bright X-ray region of the SNR in a spatiallydistinct band approximately 1° by 4° oriented approximatelynorth-south. The high-excitation C I (denoted C I* and C I**) isinterpreted as evidence of a complex of shocked dense clouds interactingwith the SNR, because of the high pressures indicated in this region. Tofurther analyze the properties of this region of enhanced C I* and CI**, we present new HIRES-processed IRAS data of the entire Vela SNR. Atemperature map calculated from the HIRES IRAS data, based on atwo-component dust model, reveals the signature of hot dust at severallocations in the SNR. The hot dust is anticorrelated spatially withX-ray emission, as would be expected for a dusty medium interacting witha shock wave. The regions of hot dust are strongly correlated withoptical filaments, supporting a scenario of dense clouds interior to theSNR that have been shocked and are now cooling behind the supernovablast wave. With few exceptions, the lines of sight to the stronghigh-excitation C I pass through regions of hot dust and opticalfilaments. Possible mechanisms for the production of the unexpectedlylarge columns of high-excitation C I are discussed. Dense clouds on theback western hemisphere of the remnant may explain the relatively lowX-ray emission in the western portion of the Vela SNR due to the slowerforward shock velocity in regions where the shock has encountered thedense clouds. An alternate explanation for the presence of ground-stateand excited-state neutrals, as well as ionized species, along the sameline of sight is a magnetic precursor that heats and compresses the gasahead of the shock.
|New periodic variables from the Hipparcos epoch photometry|
Two selection statistics are used to extract new candidate periodicvariables from the epoch photometry of the Hipparcos catalogue. Theprimary selection criterion is a signal-to-noise ratio. The dependenceof this statistic on the number of observations is calibrated usingabout 30000 randomly permuted Hipparcos data sets. A significance levelof 0.1 per cent is used to extract a first batch of candidate variables.The second criterion requires that the optimal frequency be unaffectedif the data are de-trended by low-order polynomials. We find 2675 newcandidate periodic variables, of which the majority (2082) are from theHipparcos`unsolved' variables. Potential problems with theinterpretation of the data (e.g. aliasing) are discussed.
|Interstellar CN toward CH+-forming regions|
Measurements on interstellar CN absorption are presented for stars inthree southern OB associations, NGC 2439, Vela OB1, and Cen OB1. CN isdetected in 21 out of 31 stars observed. The doublet ratio for the R(1)and P(1) lines of the (0, 0) band of the B 2Sigma+-X 2Sigma + violet system and acomparison of violet system data with measurements of the (1, 0) and (2,0) bands of the A 2Pi -X 2Sigma + redsystem are used to derive Doppler parameters and total column densities.Inferred CN column densities vary by more than an order of magnitude forlines of sight with similar CH column densities. Observations of the (0,0) band of the CH B 2Sigma --X 2Pisystem are used to revise previously published CH column densitiestoward the lines of sight studied in CN. Together with earlier resultson CH, CH+, and C2, the CN data presented hereprovide a homogeneous set of column densities and radial velocities ofdiatomic molecules in three individual translucent clouds. We use thesedata to study CN production via chemical models. Gas densities areinferred from models based on production via CH and C2 incool gas. Most sightlines in our sample test densities typical fordiffuse molecular gas (a few hundred cm-3 ) when theultraviolet flux permeating the gas is between 1 and 5 times the averageinterstellar flux. A few lines of sight indicate that CN is producedunder dark cloud conditions because relatively large densities areobtained or because this simple chemical scheme is unable to reproducethe observed CN columns. Low densities are indicated for directions withupper limits on CN. We add an ad hoc component of a number oflow-velocity (<10 km s-1) criss-crossing MHD shocks toexplain observed column densities of interstellar CH+. Theseshocks also produce about 10 to 30% of the total CH column along theline of sight.
|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 (184.108.40.206) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
|The distribution of bright OB stars in the Canis Major-Puppis-Vela region of the Milky Way|
The picture of the young stellar groups in the Canis Major-Puppis-Vela(215 deg
|Spectroscopy and Time Variability of Absorption Lines in the Direction of the Vela Supernova Remnant|
We present high-resolution (R~75,000), high signal-to-noise (S/N~100) CaII λ3933.663 and Na I λλ5889.951, 5895.924 spectraof 68 stars in the direction of the Vela supernova remnant. The spectracomprise the most complete high-resolution, high S/N optical survey ofearly-type stars in this region of the sky. A subset of the sight lineshas been observed at multiple epochs, 1993/1994 and 1996. Of the 13stars observed twice, seven have spectra revealing changes in theequivalent width and/or velocity structure of lines, most of which arisefrom remnant gas. Such time variability has been reported previously forthe sight lines toward HD 72089 and HD 72997 by Danks & Sembach andfor HD 72127 by Hobbs and coworkers. We have confirmed the ongoing timevariability of these spectra and present new evidence of variability inthe spectra of HD 73658, HD 74455, HD 75309, and HD 75821. We havetabulated Na I and Ca II absorption-line information for the sight linesin our sample to serve as a benchmark for further investigations of thedynamics and evolution of the Vela SNR. Based on observations obtainedat the European Southern Observatory, La Silla, Chile.
|B Stars as a Diagnostic of Star Formation at Low and High Redshift|
We have extended the evolutionary synthesis models by Leitherer et al.by including a new library of B stars generated from the IUEhigh-dispersion spectra archive. We present the library and show how thestellar spectral properties vary according to luminosity classes andspectral types. We have generated synthetic UV spectra for prototypicalyoung stellar populations varying the IMF and the star formation law.Clear signs of age effects are seen in all models. The contribution of Bstars in the UV line spectrum is clearly detected, in particular forgreater ages when O stars have evolved. With the addition of the newlibrary we are able to investigate the fraction of stellar andinterstellar contributions and the variation in the spectral shapes ofintense lines. We have used our models to date the spectrum of the localsuper-star cluster NGC 1705-1. Photospheric lines of C III λ1247,Si III λ1417, and S V λ1502 were used as diagnostics todate the burst of NGC 1705-1 at 10 Myr. Interstellar lines are clearlyseen in the NGC 1705-1 spectrum. Broadening and blueshifts of severalresonance lines are stronger in the galaxy spectrum than in our modelsand are confirmed to be intrinsic of the galaxy. Si II λ1261 andAl II λ1671 were found to be pure interstellar lines with anaverage blueshift of 78 km s-1 owing to a directed outflow ofthe interstellar medium. We have selected the star-forming galaxy1512-cB58 as a first application of the new models to high-z galaxies.This galaxy is at z=2.723, it is gravitationally lensed, and its highsignal-to-noise ratio Keck spectrum shows features typical of localstarburst galaxies, such as NGC 1705-1. Models with continuous starformation were found to be more adequate for 1512-cB58 since there arespectral features typical of a composite stellar population of O and Bstars. A model with Z=0.4 Zsolar and an IMF with α=2.8reproduces the stellar features of the 1512-cB58 spectrum.
|Vela OB1: Probable New Members and Hertzsprung-Russell Diagram|
Several dozen stars are identified as probable previously unrecognizedmembers of the association Vel OB1, including the Vela X-1 binary pulsarsystem. Based on a variable extinction analysis of 70 stars, thedistance and ratio of total to selective absorption of the associationare determined to be 1750 pc and 3.70, respectively. Vel OB1 may besignificantly larger than previously appreciated, perhaps up to 600 by300 pc in the sense of longitude by latitude. This physical extent, andthe fact that the H-R diagram includes both low-mass evolved yellowsupergiants and massive, early-type supergiants, indicates that Vel OB1is probably not coeval.
|The 74th Special Name-list of Variable Stars|
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.
|Interstellar C_2 absorption lines towards CH+ forming regions|
Interstellar C_2 absorption line observations towards the southern OBassociations NGC 2439, Vela OB1, and Cen OB1 are used to infergaskinetic temperatures Tkin and densities nctowards lines of sight with previously determined large CH andCH+ column densities. Towards NGC 2439, the material ischaracterised by temperatures of Tkin = 75-85 K and densitiesexceeding nc > 1000 C_2m, and a fractional C_2 abundanceof about x(C_2) = 1.5 10-8. Temperatures and densitiesinferred towards two stars in Vela OB1 are Tkin = 65-85 K andnc >= 600 C_2m. C_2 fractional abundances in the cloudcomplex obscuring Vela OB1 are about half the value found in NGC 2439.For the lines of sight towards Cen OB1, values of Tkin =70-95 K and fractional abundances of x(C_2) ~ 5 10-9 arefound, and towards HD 114213, Tkin = 25 K and nc =400+/-100 C_2m. The observations demonstrate that C_2 resides in coolgas at temperature of Tkin < 100 K. The C_2 columndensities are correlated with those of CH, which is expected fromtheoretical models. This suggests that CH is efficiently formed in thecool material as well, together with C_2. This finding does not supportexpectations from recent MHD and vortex models of CH+formation, which stipulate that neutrals such as CH are abundantlyproduced in hot regions of many 100 K temperature.
|UBV beta Database for Case-Hamburg Northern and Southern Luminous Stars|
A database of photoelectric UBV beta photometry for stars listed in theCase-Hamburg northern and southern Milky Way luminous stars surveys hasbeen compiled from the original research literature. Consisting of over16,000 observations of some 7300 stars from over 500 sources, thisdatabase constitutes the most complete compilation of such photometryavailable for intrinsically luminous stars around the Galactic plane.Over 5000 stars listed in the Case-Hamburg surveys still lackfundamental photometric data.
|An extensive Delta a-photometric survey of southern B and A type bright stars|
Photoelectric photometry of 803 southern BS objects in the Deltaa-system as detection tool for magnetic chemically peculiar (=CP2) starshas been carried out and compared to published spectral types. Thestatistical yield of such objects detected by both techniques ispractically the same. We show that there are several factors whichcontaminate the search for these stars, but this contamination is onlyof the order of 10% in both techniques. We find a smooth transition fromnormal to peculiar stars. Our sample exhibits the largest fraction ofCP2 stars at their bluest colour interval, i.e. 10% of all stars in thecolour range -0.19 <= B-V < -0.10 or -0.10 <= b-y < -0.05.No peculiar stars based on the Delta a-criterion were found at bluercolours. Towards the red side the fraction of CP2 stars drops to about3% for positive values of B-V or b-y with red limits roughlycorresponding to normal stars of spectral type A5. The photometricbehaviour of other peculiar stars: Am, HgMn, delta Del, lambda Boo, Heabnormal stars, as well as Be/shell stars and supergiants shows someslight, but definite deviations from normal stars. Spectroscopic andvisual binaries are not distinguished from normal stars in their Delta abehaviour. The results of this work justify larger statistical work(e.g. in open clusters) employing more time-saving photometric methods(CCD). \newpage Based on observations obtained at the European SouthernObservatory, La Silla, Chile. This research has made use of the Simbaddatabase, operated at CDS, Strasbourg, France. Table 2 is only availablein electronic form via anonymous ftp 220.127.116.11 orhttp://cdsweb.u-strasbg.fr/Abstract.html
|Red and infrared colours of B stars and the reddening law in the Galaxy|
The red and infrared intrinsic colours of B stars are derived fromphotometric observations through the UBV(RI)_CJHK and Hβ filters of257 early-type stars. Those stars for which the UBV and Hβmeasurements match the published spectral class, and which show no othersigns of peculiarity, are used to determine the intrinsic photometriccolours of B stars in the red and infrared. From these intrinsic coloursthe interstellar reddening relationships for the red and infraredcolours are evaluated, and the results are compared with previousestimates of these quantities. The values of R, E(B-V) and the distanceare then determined for the individual stars. R is confirmed to be closeto 3.1 in most cases, but was found to be much larger in somedirections. The relationship between R and the location of a star in theGalaxy is investigated. Usually the abnormally reddened stars seemed tobe associated with known regions of star formation. The paper alsoidentifies seven likely variable stars and a number of stars withpossible dust shells.
|Cross-correlation characteristics of OB stars from IUE spectroscopy|
We present a catalogue of homogeneous measures of the linewidthparameter, v_esin i, for 373 O-type stars and early B supergiants(including the separate components of 25 binary and three triplesystems), produced by cross-correlating high-resolution,short-wavelength IUE spectra against a `template' spectrum of tauSco. Wealso tabulate terminal velocities. There are no O supergiants in oursample with v_esin i<65 km s^-1, and only one supergiant earlier thanB5 has v_esin i<50 km s^-1, confirming that an important linebroadening mechanism in addition to rotation must be present in theseobjects. A calibration of the area under the cross-correlation peakagainst spectral type is used to obtain estimates of continuum intensityratios of the components in 28 spectroscopically binary or multiplesystems. At least seven SB2 systems show evidence for the `Struve-Sahadeeffect', a systematic variation in relative line strength as a functionof orbital phase. The stellar wind profiles of the most rapid rotator inour sample, the O9III:n* star HD 191423 (v_esin i=436km s^-1), show itto have a `wind-compressed disc' similar to that of HD 93521; this starand other rapid rotators are good candidates for studies of non-radialpulsation.
|A Radial Velocity Database for Stephenson-Sanduleak Southern Luminous Stars|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....113..823R&db_key=AST
|Interstellar CH^+^ in southern OB associations.|
Optical absorption line observations of interstellar CH^+^ and CH arepresented towards the southern OB associations CMa OB1, NGC 2439, VelaOB1, NGC 4755, and Cen OB1. A total of 5-11 stars per association wereobserved, with visual extinctions ranging from A_V_=0.5-4.5mag. Thederived CH^+^ and CH velocities agree within the measurement errors.Towards a particular association, the CH^+^ column density N(CH^+^) iscorrelated to the visual extinction of the background star. Thesefindings weaken the possibility that magnetic shocks are the generalmechanism that is required to produce interstellar CH^+^. It is foundthat N(CH^+^) is correlated to N(CH), which indicates that N(CH^+^) iscorrelated to the optical depth of a cloud. The correlations aredifficult to reconcile with scenarios where the sites of CH^+^ formationare constrained to the surface of molecular clouds. The observationssupport ideas which involve turbulence as a major CH^+^ productionmechanism. In particular, the results are in agreement with expectationsfrom a scenario where the CH^+^ formation proceeds in cool gas via afraction of fast, non-Maxwellian H_2_ or C^+^, created by thedissipation of interstellar turbulence.
|A Spectral Atlas of Hot, Luminous Stars at 2 Microns|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJS..107..281H&db_key=AST
|The ROSAT all-sky survey catalogue of optically bright OB-type stars.|
For the detailed statistical analysis of the X-ray emission of hot starswe selected all stars of spectral type O and B listed in the Yale BrightStar Catalogue and searched for them in the ROSAT All-Sky Survey. Inthis paper we describe the selection and preparation of the data andpresent a compilation of the derived X-ray data for a complete sample ofbright OB stars.
|Observations of diffuse interstellar bands and of interstellar polarization|
|A spectroscopic database for Stephenson-Sanduleak Southern Luminous Stars|
A database of published spectral classifications for objects in theStepenson-Sanduleak Luminous Stars in the Southern Milky Way catalog hasbeen compiled from the literature. A total of 6182 classifications for2562 stars from 139 sources are incorporated.
|Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.|
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
|Interstellar NaI absorption towards stars in the region of the IRAS VELA shell.|
|An atlas of ultraviolet P Cygni profiles|
We have selected spectra of 232 stars from the International UltravioletExplorer (IUE) archives for inclusion in an atlas intended for varioususes but tailored especially for the study of stellar winds. The atlascovers the range in spectral types from O3 to F8. The full atlas coversthe reduced and normalized high resolution spectra from the IUE long-and short-wavelength spectrographs. Here we discuss the selection of thestars and the data reduction, and we present in velocity units theprofiles of lines formed in the stellar winds. The selected lines covera wide range of ionizations, allowing a comparison of the profiles fromdifferent ions in the wind of each star and a comparison of thedifferent wind lines as a function spectral type and luminosity. We alsopresent the basic data on the program stars to facilitate study of thedependence of wind features on stellar parameters such as luminosity,temperature, escape velocity, and v sin i. We provide an overview of thecharacteristic behavior of the wind lines in the H-R diagram. Thecomplete spectra are available in digital form through the NASAAstrophysics Data System (ADS). We offer a description of the electronicdatabase that is available through the ADS and guidelines for obtainingaccess to that database.
|Chemical transitions for interstellar C2 and CN in cloud envelopes|
Observations were made of absorption from CH, C2, and CN towardmoderately reddened stars in Sco, OB2, Ceo OB3, and Taurus/Auriga. Forthese directions, most of the reddening is associated with a singlecloud complex, for example, the rho Ophiuchus molecular cloud, and as aresult, the observations probe moderately dense material. When combinedwith avaliable data for nearby directions, the survey provides the basisfor a comprehensive analysis of the chemistry for these species. Thechemical transitions affecting C2 and CN in cloud envelopes wereanalyzed. The depth into a cloud at which a transition takes place wascharacterized by tauuv, the grain optical depth at 1000 A.One transition at tauuv approx. = 2, which arises from, theconversion of C(+) into CO, affects the chemistries for both moleculesbecause of the key role this ion plays. A second one involvingproduction terms in the CN chemistry occurs at tauuv ofapprox. = 3; neutral reactions which C2 and CH is more important atlarger values for tauuv. The transition fromphotodissociation to chemical destruction takes place attauuv approx. = 4.5 for C2 and CN. The observational data forstars in Sco OB2, Cep OB3, and Taurus/Auriga were studied with chemicalrate equations containing the most important production and destructionmechanisms. Because the sample of stars in Sco OB2 includes sight lineswith Av ranging from 1-4 mag, sight lines dominated byphotochemistry could be analyzed separately from those controlled bygas-phase destruction. The analysis yielded values for two poorly knownrate constants for reactions involved in the production of CN; thereactions are C2 + N yields CN + C and C(+) + NH yields all products.The other directions were analyzed with the inferred values. Thepredicted column densities for C2 and CN agree with the observed valuesto better than 50%, and in most instances 20%. When combining theestimates for density and temperature derived from chemical modeling andmolecular excitation for a specific cloud, such as the rho Ophiuchusmolecular cloud, the portion of the cloud envelope probed by C2 and CNabsorption was found to be in pressure equilibrium.
|Millimetre observations of southern translucent clouds|
Millimetre emission line observations of ^12^CO J=1-0 are presented fora sample of translucent molecular clouds previously studied by opticalabsorption lines towards background stars. The CO maps provideinformation on the extent, structure, mass and kinematics of theregions. In some clouds, the emission is characterized by a singlecomponent which does not vary much across the region. In other cases,multiple close-lying components or sheets are found, which may vary in aself-similar manner across the cloud. None of the clouds is close tosimple virial equilibrium. Sensitive searches for ^13^CO and C^18^OJ=1-0 emission have been made towards the stellar positions. C^18^O hasbeen detected in only 5 clouds, most of which have extinctions well inexcess of 2 mag. The inferred ^13^CO/C^18^O abundance ratios range from7-25, and the lower limits from >13 to >35. These values are asmuch as five times larger than the overall interstellar([^13^C].[^16^O])/([^12^C] .[^18^O]) ratio, suggesting thatisotope-selective photodissociation plays a role in at least some of theclouds. Searches for other molecules at millimetre wavelengths have beenmade for a few of the best characterized clouds. Surprisingly, noemission was detected from the C_2_H or C_3_H_2_ molecules, even thoughthe abundances of diatomic C_2_ and CH are quite large. On the otherhand, the abundance of HCO^+^ appears comparable to that found in denserclouds, and the abundance of HCN may be up to an order of magnitudelarger than the predictions of models in two clouds.
|The distribution of interstellar dust in the solar neighborhood|
We surveyed the IRAS data base at the positions of the 1808 O6-B9.5stars in The Bright Star Catalog for extended objects with excessemission at 60 microns, indicating the presence of interstellar dust atthe location of the star. Within 400 pc the filling factor of theinterstellar medium, for dust clouds with a density greater than 0.5/cucm is 14.6 + or - 2.4%. Above a density of 1.0/cu cm, the densitydistribution function appears to follow a power law index - 1.25. Whenthe dust clouds are mapped onto the galactic plane, the sun appears tobe located in a low-density region of the interstellar medium of widthabout 60 pc extending at least 500 pc in the direction of longitudes 80deg - 260 deg, a feature we call the 'local trough'.
|Bright blue stars in VELA observed with the 'Glazar' space telescope|
Seventy-one stars brighter than about 9 m have been detected at 1640 Ain the Vela region with the space telescope Glazar. It is shown thatmost of the detected stars belong to a B-type stellar association at adistance of 460 pc and to two OB stellar associations at distances of1100 pc and 1700 pc. The existence of B-type stellar association at adistance of 110 pc is suspected. A new O-type star cluster, which is apossible nucleus of the OB stellar association at 1700 pc, has beendetected. The distribution of the absorbing matter in the observed areais studied. We presume that the stars HD 75 063 and 76 534 are probablyembedded in a circumstellar dust shell. All observed stars, includingthose with unknown spectra, are early type stars.
|An Einstein Observatory SAO-based catalog of B-type stars|
About 4000 X-ray images obtained with the Einstein Observatory are usedto measure the 0.16-4.0 keV emission from 1545 B-type SAO stars fallingin the about 10 percent of the sky surveyed with the IPC. Seventy-fourdetected X-ray sources with B-type stars are identified, and it isestimated that no more than 15 can be misidentified. Upper limits to theX-ray emission of the remaining stars are presented. In addition tosummarizing the X-ray measurements and giving other relevant opticaldata, the present extensive catalog discusses the reduction process andanalyzes selection effects associated with both SAO catalog completenessand IPC target selection procedures. It is concluded that X-rayemission, at the level of Lx not less than 10 exp 30 ergs/s, is quitecommon in B stars of early spectral types (B0-B3), regardless ofluminosity class, but that emission, at the same level, becomes lesscommon, or nonexistent, in later B-type stars.
|Photospheric Absorption Lines in the Ultraviolet Spectra of O-Stars and B-Stars|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990MNRAS.246..392P&db_key=AST
|Interstellar C2, CH, and CN in translucent molecular clouds|
Optical absorption-line techniques have been applied to the study of anumber of translucent molecular clouds in which the total columndensities are large enough that substantial molecular abundances can bemaintained. Results are presented for a survey of absorption lines ofinterstellar C2, CH, and CN. Detections of CN through the A 2Pi-X2Sigma(+) (1,O) and (2,O) bands of the red system are reported andcompared with observations of the violet system for one line of sight.The population distributions in C2 provide diagnostic information ontemperature and density. The measured column densities of the threespecies can be used to test details of the theory of molecule formationin clouds where photoprocesses still play a significant role. The C2 andCH column densities are strongly correlated with each other and probablyalso with the H2 column density. In contrast, the CN column densitiesare found to vary greatly from cloud to cloud. The observations arediscussed with reference to detailed theoretical models.
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|Constellation:||Segel des Schiffs|
|Proper motion RA:||-5.6|
|Proper motion Dec:||3.9|
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