Eduardo Amores

Title: An analysis of stellar population of the galactic bar

We present observations using the infrared camera (CAMIV) at LNA - Brazil. Our main objective is to better characterize the population of the spiral arms and the galactic bar (located in galactic longitudes l ~ + 23º and l ~ -14º). We present color-color and color mangitude of the bar extremities (J, H and K bands). Our observations is around 1.5 mag deeper than the 2MASS data.

Zoltan Balog

Title: Near IR survey of NGC7538

We show the results of two near infrared (K-band) imaging surveys and a JHK survey of the vicinity of NGC~7538. We identify more than 2000, 9000 and 786 near-infrared sources on the images of the two K-band surveys and the JHK survey respectively. From color-color diagrams, we derive a reddening law for background stars and identify 238 stars with NIR excesses. Contour maps indicate a high density peak coincident with a concentration of stars with NIR excesses. We identify this peak as a young, embedded cluster and confirm this result with the K-band luminosity function, color histograms, and color-magnitude diagrams. For an adopted distance, d ~ 2.8 kpc, and reddening, E_{J-K} = 0.55, the slope of the logarithmic K-band luminosity function (KLF),s ~ 0.32, agrees well with previous results for other regions.

Sylvain Bontemps

Title: Survey for massive protostars in Cygnus X

From near-IR to far-IR online data as well as from a complete millimeter continuum imaging of the Cygnus X molecular complex, we could derive a full census for proto-OB stars from the earliest phases of evolution to UCHII regions. We will draw the results of this unique statistical work in a single molecular complex aiming at deriving the timeline of massive star formation.

Sukanya Chakrabarti

Title: SEDs of Dusty Sources: Analytic Models for Unresolved Objects

We present analytic radiative transfer solutions for the dust thermal spectrum of unresolved objects. We focus specfically on massive protostars, but our methodolgy is also applicable to dust-enshrouded AGN and dusty starbusts. We have compared our analytic solutions to a well-tested radiative transfer code, DUSTY, and find excellent agreement with the numerical results. We present our analytic fits for three well known regions of massive star formation, namely, the Orion hot core, IRAS 20126+4104, and IRAS 23385+6053. We also present fits for ULIRG data obtained from the Spitzer First Look Survey. The goal is to use the analytic model to facilitate the interpretation of observations of massive star forming regions as well as extragalactic sources. In particular, this approach allows us to use SEDs as a diagnostic tool in inferring physical conditions in massive cores and to discriminate between competing theories of star formation.

Carlos Eiroa

Title: VLA radio continuum sources in the Serpens cloud core

The Serpens cloud core is a nearby, active star forming region where a rich cluster of Class O, Class I and Class II objects is found. We present a list of VLA radio continuum sources detected in the cloud core. Associations with objects at other wavelength regimes are discussed.

Fabiana Faustini

Title: Properties of stellar cluster around High-Mass star formation

Twenty-seven high-luminosity IRAS sources believed to be in the early phases of high-mass star formation have been observed in the Near-IR (J, H, Ks) to characterise the clustering properties of their young stellar population and compare them with those of more evolved objects (e.g., Herbig Ae/Be stars). All the observed sources possess strong line and continuum emission in the millimetre, being therefore associates with gas and dust envelopes. Ten sources have Far-IR colours characteristic of UCHII regions while the other 17 are likely being experiencing an evolutionary phase that precedes the Hot-Cores, as suggested by a variety of evidence collected in the past decade. Twenty-four sources show evidence of clustering with a stellar richness that varies from few objects to hundreds of objects. For each cluster we carried out aperture photometry, including a correction for the confusion effects, and derived Stellar density profiles, color-color and color-magnitude diagrams, and luminosity functions.

Bruno Ferreira

Title: Cluster Recognition Program, Results of a Systematic Survey of Embedded Clusters

Only by studying many clusters can we obtain statistically sound conclusions as to their properties. The Cluster Recognition Program (CRP) was made to detect clusters systematically thus avoiding biases and increasing detection efficient. Simultaneously, the CRP obtains fundamental cluster parameters: KLF, structure, size, number of members, and cluster IMF.

Yohei Harayama

Title: Study of the IMF of the Galactic Star-forming regions from VLT adaptive optics observations

We present our preliminary results of the IMF of the massive star-forming regions W51 and Quintuplet cluster from the NIR observations using the NAOS/CONICA adaptive optics at the VLT. We will also discuss resutls from analysis of the IMF of the NGC 3603 focussing particularly on low-mass regime down to the hydrogen burning limit.

Susana Iglesias-Groth

Title: Extinction and Electric dipole emission by fullerenes in star forming regions

Fullerenes have been proposed as a possible carrier of the UV 217.5 nm bump in the extinction curve (Iglesias-Groth,S. 2004 ApJLett 608,37 ). We discuss how these rapidly rotating molecules could produce electric dipole microwave emission with a characteristic spectrum which would be measurable and disentangled from free-free emission in dusty clouds and HII regions.

Anne-Katharina Jappsen

Title: Mass Spectra from Gravoturbulent Fragmentation: Effects of the Equation of State

One of the major uncertanties in identifying the processes that determine the initial mass function (IMF) of stars is the exact chemical state of the star forming gas and its influence on the dynamical evolution. We study the effects of a piecewise polytropic equation of state on the formation of stellar clusters in turbulent, self-gravitating molecular clouds using three-dimensional, smoothed particle hydrodynamics simulations.

Eric Keto

Title: The gravitational and thermal stability of starless and prestellar cores

Hydrodynamic models of the evolution of dark cloud cores that include the effect of radiative cooling on the dynamics suggest that the dark cloud cores are subject to two types of instability. The first is the well known gravitational instability that has been studied in isothermal, hydrostatically supported (Bonner-Ebert) spheres. The second instability is a type of global thermal instability that arises from the radiative equilibrium of the gas and dust. The critical densities of the two instabilities occur at about the same value and effectively divide the dark cloud cores into two classes matching the observational classifications of "starless" and "prestellar". In the first class are warmer, less dense cores that are long-lived and stable, although possibly oscillating. In the second class are colder, denser cores that are collapsing to form protostars. Model spectral line profiles calculated from the hydrodynamic models match the observations of cores in the two classes. In particular, modeled CS and N2H+ spectra from a hydrodynamic simulation of a stable oscillating cloud match recent observations of the red and blue asymmetric spectral lines seen in the starless core B68. Model spectra from a hydrodynamic simuation of a gravitationally unstable cloud match the infall spectra of the prestellar core L1544.

M.S. Nanda Kumar, U.S. Kamath and C. J. Davis

Title: Embedded Clusters in W51 Gaint Molecular Cloud

We present sub-arcsecond (0.35"-0.9"), near-infrared J,H,K band photometric observations of six fields along the W51 Giant Molecular Cloud (W51 GMC). Our observations reveal four new, embedded clusters and provide a new high-resolution (0.35") view of the W51IRS2 (G49.5-0.4) region. The cluster associated with G48.9-0.3 is found to be a double cluster enclosed in a nest of near-infrared nebulosity. We construct stellar surface density maps for four major clusters in the W51 GMC. These unveil the underlying hierarchical structure. Color-color and color-magnitude diagrams for each of these clusters show clear differences in the embedded stellar populations and indicate the relative ages of these clusters. In particular, the clusters associated with the HII regions G48.9-0.3 and G49.0-0.3 are found to have a high fraction of YSOs and are therefore considered the youngest of all the near-infrared clusters in the W51 GMC. The estimated masses of the individual clusters, when summed, yield a total stellar mass of $\sim$10$^4$\msun\ in the W51 GMC, implying a star formation efficiency of 5-10\%. These results in comparision with the CO observations of the W51 GMC, suggest for the first time, that star formation in the W51 GMC is likely triggered by a galactic spiral density wave.

Michael R. Meyer and Julia Greissl

Title: Constraining the IMF in Extreme Environments: Direct Detection of Young Low Mass Stars in Unresolved Starbursts

We demonstrate the feasibility of detecting directly low mass stars in unresolved super-star clusters with ages < 10 Myr using near-infrared spectroscopy at modest resolution (R ~ 1000). Such measurements could constrain the ratio of high to low mass stars in these extreme star-forming events, providing a direct test on the universal nature of the initial mass function (IMF) compared to the disk of the Milky Way (Chabrier, 2003). We compute the integrated light of super-star clusters with masses of 10^4, 10^5, and 10^6 Msun drawn from the Salpeter (1955) and Kroupa (2001) IMFs for clusters aged 1, 3, and 10 Myr. We combine, for the first time, results from Starburst99 (Leitherer et al. 1999) for the main sequence and post--main sequence population (including nebular emission) with pre-main sequence (PMS) evolutionary models (Siess et al. 2000) for the low mass stars as a function of age. We show that ~ 10-20 % of the integrated light observed at 2.2 microns comes from low mass PMS stars with late-type stellar absorption features at ages < 10 Myr. This light is detectable using high signal-to-noise spectra (> 100) at R=1000 placing constraints on the ratio of high to low mass stars contributing to the integrated light of the cluster.

Oscar Morata

Title: Evidence for transient clumps and gas chemical evolution in the CS core of L673

We present combined BIMA and FCRAO maps of the high density molecular emission towards the L673 starless core. We find several intense fully resolved clumps. We propose that most of these clumps are transient, and only the more massive ones could last long enough to form stars.

Ko Nedachi

Title: A Comprehensive Study of the Corona Australis Star-Forming Region

The CrA star-forming region is an ideal place to conduct a detailed case study of cluster-mode star-formation because of its extreme youth, compactness, relatively simple morphology, and its close distance from us. I will present the results from our on-going comprehensive study of the region in NIR and thermal IR wavelengths.

Linda Podio

Title: Potential of a combined VIS/NIR diagnostic for protostellar jets

Supersonic protostellar jets are an essential element to understand obscure aspects of the star formation process. To fully exploit the capabilities of the new instruments being developed for high angular resolution and interferometry, one has to start from a firm knowledge of the average physical properties of the targets. To this aim we have studied the conditions of the plasma along a number of \

Nicola Schneider

Title: A large-scale survey of the high-mass star forming molecular clouds in Cygnus X

In order to probe the processes by which rich clusters and high-mass stars form, the most active nearby GMCs need to be studied in different wavelengths. We thus present a molecular line survey (13CO 3-2,2-1,1-0, C18O 1-0, CS 2-1, N2H+ 1-0) of the Cygnus X region, using the FCRAO and KOSMA radiotelescopes in order to reveal the velocity and spatial structure of the molecular gas and to determine its physical properties.

M. Tafalla, J. Santiago, D. Johnstone & R. Bachiller

Title: A highly collimated, extremely high velocity outflow in Taurus

We present the first case of a highly collimated, extremely high velocity bipolar outflow in Taurus. It is powered by the low-luminosity (0.4 $L_\odot$) source IRAS 04166+2706 and contains gas accelerated up to 50 km s$^{-1}$ with respect to the ambient cloud both toward the blue and the red (uncorrected for projection). At the highest velocities, the outflow collimation factor exceeds 20, and the gas displays a very high degree of spatial symmetry. This very fast gas presents multiple maxima, and most likely arises from the acceleration of ambient material by a time-variable jet-like stellar wind. When scaled for luminosity, the outflow parameters of IRAS 04166 are comparable to those of other extremely high velocity outflows like L1448, indicating that even the very quiescent star-formation mode of Taurus can produce objects powering very high energy flows ($L_{mec}/L_* > 0.15$).

Paula Teixeira

Title: Revealing the structure of Lupine darkness

How do filamentary clouds form evolve to produce stars? We have obtained deep NIR observations of a dense, starless region of the Lupus cloud (ESO's NTT and VLT) in order to address this question by constructing a dust extinction map and examining the detailed internal structure of this prime example of a filamentary dark cloud.

Sarita Vig

Title: Infrared study of the southern Galactic star forming region associated with IRAS 10049-5657

The southern Galactic star forming region associated with IRAS 10049-5657 has been mapped simultaneously in two far infrared bands ($\lambda_eff$ = 148 \& 209 $\mu$m), with $\sim 1'$ angular resolution using the TIFR 1-m balloon borne telescope. Spatial distribution of the temperature of cool dust and optical depth at 200 micron, have been obtained taking advantage of the similar beams in the two bands. The HIRES processed IRAS maps at 12, 25, 60 & 100 micron have been used for comparison. The distribution of warm dust and emission in Unidentified Infrared Bands in the mid infrared, have been studied based on the MSX data. Radiative transfer modelling has been carried out taking into account all available infrared and radio measurements to obtain various physical parameters like nature of the exciting source, geometrical dimensions, dust distribution and composition etc.

Beletsky Yuri

Title: Mapping extragalactic molecular clouds: Centaurus A (NGC 5128)

The physics of the formation of GMCs is one of the major unsolved problems of the interstellar medium. Using dust extinction as a tracer of H 2 we study the physical structure of a complete sample of GMCs at different evolutionary status in the nearby galaxy NGC5128 (Centaurus A). We present photometrically calibrated JHK images of Centaurus A. Color maps of the images are derived using an optimized multi-band NICER technique (Lombardi & Alves 2001). From these data pixel-by-pixel maps of the distribution of dust extinction for the galaxy is derived.