
Aurora Sicilia-Aguilar- Dr.
- University of Dundee
Aurora Sicilia-Aguilar
- Dr.
- University of Dundee
Reader &
SUPA Theme Leader for Astronomy & Space Science
About
148
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Introduction
I work on star formation and protoplanetary disk evolution using multiwavelength observations (from optical to millimeter data). I am specially interested in the evolution of protoplanetary disks, which different paths of evolution we can observe (and their potential consequences to planet formation), and where the diversity of disks we observe comes from (initial conditions, environment in the star-forming region).
Current institution
Additional affiliations
January 2017 - present
November 2015 - December 2016
October 2013 - October 2015
Publications
Publications (148)
EX Lupi is a young star, prototype of EXor variables. Its spectrum is very
rich in emission lines, including many metallic lines. It has been also
proposed to have a close companion. We use the metallic emission lines to study
the accretion structures and to test the companion hypothesis. We analyse 54
spectra taken in 5 years of quiescence time. W...
Recent progress in telescope development has brought us different ways to observe protoplanetary disks: interferometers, space missions, adaptive optics, polarimetry, and time- and spectrally-resolved data. While the new facilities have changed the way we can tackle open problems in disk structure and evolution, there is a substantial lack of inter...
(Abridged) IC1396A is a cometary globule containing the Class 0 source IC1396A-PACS-1. We use IRAM 30m and Gaia DR2 data to explore the star-formation history of IC1396A and investigate the possibilities of triggered star formation. IRAM and Herschel continuum data reveal dust temperatures and column densities. Heterodyne data reveal the velocity s...
Context. RX J1604.3-2130A is a young, dipper-type, variable star in the Upper Scorpius association, suspected to have an inclined inner disk, with respect to its face-on outer disk.
Aims. We aim to study the eclipses to constrain the inner disk properties.
Methods. We used time-resolved photometry from the Rapid Eye Mount telescope and Kepler 2 dat...
Aims. We use optical spectroscopy to investigate the disk, wind, and accretion during the 2008 Z CMa NW outburst.
Methods. Emission lines were used to constrain the locations, densities, and temperatures of the structures around the star.
Results. More than 1000 optical emission lines reveal accretion, a variable, multicomponent wind, and double-pe...
Context. It is well established that classical T Tauri stars accrete material from a circumstellar disk through magnetic fields. However, the physics regulating the processes in the inner (0.1 AU) disk is still not well understood.
Aims. Our aim is to characterize the accretion process of the classical T Tauri Star RU Lup.
Methods. Optical high-res...
The aim of this work is to characterize the accretion process of the classical T Tauri Star RU Lup. We studied optical high-resolution spectroscopic observations from CHIRON and ESPRESSO, obtained simultaneously with photometric data from AAVSO and TESS. We detected a periodic modulation in the narrow component of the He I 5876 line with a period t...
We present the overview and first results from the North-PHASE Legacy Survey, which follows six young clusters for five years, using the 2 deg$^2$ FoV of the JAST80 telescope from the Javalambre Observatory (Spain). North-PHASE investigates stellar variability on time-scales from days to years for thousands of young stars distributed over entire cl...
We present the overview and first results from the North-PHASE Legacy Survey, which follows six young clusters for five years, using the 2 deg$^2$ FoV of the JAST80 telescope from the Javalambre Observatory (Spain). North-PHASE investigates stellar variability on timescales from days to years for thousands of young stars distributed over entire clu...
Context . Nearby associations are ideal regions to study coeval samples of protoplanetary and debris disks down to late M-type stars. Those aged 5–10 Myr, where most of the disk should have already dissipated forming planets, are of particular interest.
Aims . We present the first complete study of both protoplanetary and debris disks in a young re...
We examine the long-term spectroscopic and photometric variability of EX Lupi and TW Hya, studying the presence of stable accretion and the role it plays in the observed variability. Analysing the velocity modulations of the emission lines with star-melt, we obtain information on the structure of the accretion columns and the disc–star connection....
PDS 70 is so far the only young disk where multiple planets have been detected by direct imaging. The disk has a large cavity when seen at submillimeter and near-infrared wavelengths, which hosts two massive planets. This makes PDS 70 the ideal target to study the physical conditions in a strongly depleted inner disk shaped by two giant planets, an...
Context. EX Lupi is the prototype by which EXor-type outbursts have been defined. It has experienced multiple accretion-related bursts and outbursts throughout the past decades, and the study of these events has greatly extended our knowledge about their effects. Notably, this star experienced a new burst in 2022.
Aims. We aim to investigate whethe...
PDS 70 is so far the only young disc where multiple planets have been detected by direct imaging. The disc has a large cavity when seen at sub-mm and NIR wavelengths, which hosts two massive planets. This makes PDS 70 the ideal target to study the physical conditions in a strongly depleted inner disc shaped by two giant planets, and in particular t...
EX Lupi is the prototype by which EXor-type outbursts were defined. It has experienced multiple accretion-related bursts and outbursts throughout the last decades, whose study have greatly extended our knowledge about the effects of these types of events. This star experienced a new burst in 2022. We used multi-band photometry to create color-color...
Absorption features in stellar atmospheres are often used to calibrate photocentric velocities for the kinematic analysis of further spectral lines. The Li feature at ∼6708 Å is commonly used, especially in the case of young stellar objects, for which it is one of the strongest absorption lines. However, this complex line comprises two isotope fine...
Absorption features in stellar atmospheres are often used to calibrate photocentric velocities for kinematic analysis of further spectral lines. The Li feature at $\sim$ 6708 {\AA} is commonly used, especially in the case of young stellar objects for which it is one of the strongest absorption lines. However, this is a complex line comprising two i...
Aims. We investigate the star formation history of the IC1396 region by studying its kinematics and completing the population census.
Methods. We used multiwavelength data, combining optical spectroscopy to identify and classify new members and near-infrared photometry to trace shocks, jets, and outflows as well as the interactions between the clus...
We investigate the star formation history of the IC1396 region by studying its kinematics and completing the population census. We use multiwavelength data, combining optical spectroscopy (to identify and classify new members), near-infrared photometry (to trace shocks, jets, and outflows and the interactions between the cluster members and the clo...
The Hubble UV Legacy Library of Young Stars as Essential Standards (ULLYSES) Director's Discretionary Program of low-mass pre-main-sequence stars, coupled with forthcoming data from ALMA and JWST, will provide the foundation to revolutionize our understanding of the relationship between young stars and their protoplanetary disks. A comprehensive ev...
The Hubble UV Legacy Library of Young Stars as Essential Standards (ULLYSES) Director's Discretionary Program of low-mass pre-main-sequence stars, coupled with forthcoming data from ALMA and JWST, will provide the foundation to revolutionize our understanding of the relationship between young stars and their protoplanetary disks. A comprehensive ev...
We introduce the STAR-MELT Python package that we developed to facilitate the analysis of time-resolved emission line spectroscopy of young stellar objects. STAR-MELT automatically extracts, identifies and fits emission lines. We summarise our analysis methods that utilises the time domain of high-resolution stellar spectra to investigate variabili...
We introduce the STAR-MELT Python package that we developed to facilitate the analysis of time-resolved emission line spectroscopy of young stellar objects. STAR-MELT automatically extracts, identifies and fits emission lines. We summarise our analysis methods that utilises the time domain of high-resolution stellar spectra to investigate variabili...
The evolution of young stars and disks is driven by the interplay of several processes, notably the accretion and ejection of material. These processes, critical to correctly describe the conditions of planet formation, are best probed spectroscopically. Between 2020 and 2022, about 500orbits of the Hubble Space Telescope (HST) are being devoted in...
We use Gaia DR2 data to survey the classic Monoceros OB1 region and look for the existence of a dispersed young population, co-moving with the cloud complex. An analysis of the distribution of proper motions reveals a 20–30 Myr association of young stars, about 300–400 pc away from the far side of the Mon OB1 complex, along the same general line of...
The evolution of young stars and disks is driven by the interplay of several processes, notably the accretion and ejection of material. These processes, critical to correctly describe the conditions of planet formation, are best probed spectroscopically. Between 2020 and 2022, about 500orbits of the Hubble Space Telescope (HST) are being devoted in...
The evolution of young stars and disks is driven by the interplay of several processes, notably accretion and ejection of material. Critical to correctly describe the conditions of planet formation, these processes are best probed spectroscopically. About five-hundred orbits of the Hubble Space Telescope (HST) are being devoted in 2020-2022 to the...
We use Gaia DR2 data to survey the classic Monoceros OB1 region and look for the existence of a dispersed young population, co-moving with the cloud complex. An analysis of the distribution of proper motions reveals a 20-30 Myr association of young stars, about 300-400 pc away from the far side of the Mon OB1 complex, along the same general line-of...
Extreme outbursts in young stars may be a common stage of pre-main-sequence stellar evolution. These outbursts, caused by enhanced accretion and accompanied by increased luminosity, can also strongly impact the evolution of the circumstellar environment. We present Atacama Large Millimeter Array (ALMA) and Very Large Array observations of EX Lupi,...
(Abridged) We use optical spectroscopy to investigate the disk, wind, and accretion during the 2008 ZCMa NW outburst. Over 1000 optical emission lines reveal accretion, a variable, multi-component wind, and double-peaked lines of disk origin. The variable, non-axisymmetric, accretion-powered wind has slow ($\sim $0 km s$^{-1}$), intermediate ($\sim...
Extreme outbursts in young stars may be a common stage of pre-main-sequence stellar evolution. These outbursts, caused by enhanced accretion and accompanied by increased luminosity, can also strongly impact the evolution of the circumstellar environment. We present ALMA and VLA observations of EX Lupi, a prototypical outburst system, at 100 GHz, 45...
(Abridged) We use optical spectroscopy to investigate the disk, wind, and accretion during the 2008 ZCMa NW outburst. Over 1000 optical emission lines reveal accretion, a variable, multi-component wind, and double-peaked lines of disk origin. The variable, non-axisymmetric, accretion-powered wind has slow ($\sim $0 km s$^{-1}$), intermediate ($\sim...
Context. Taurus represents an ideal region to study the three-dimensional distribution of the young stellar population and relate it to the associated molecular cloud. Aims. The second Gaia data release (DR2) enables us to investigate the Taurus complex in three dimensions, starting from a previously defined robust membership. The molecular cloud s...
Context. Taurus represents an ideal region to study the three-dimensional distribution of the young stellar population and relate it to the associated molecular cloud.
Aims. The second Gaia data release (DR2) enables us to investigate the Taurus complex in three dimensions, starting from a previously defined robust membership. The molecular cloud s...
EX Lup is the prototype of a class of pre-main-sequence eruptive stars defined by their repetitive outbursts lasting several months. In 2008 January–September EX Lup underwent its historically largest outburst, brightening by about 4 mag in visual light. In previous studies we discovered ongoing silicate crystal formation in the inner disk during t...
Introducing STAR-MELT: STellar AccRetion-Mapping with Emission Line Tomography - a Python package for extraction, identification, fitting and analysis of spectral lines
Low- and intermediate-mass stars acquire most of their mass in the protostellar phase, but accretion continues into the pre-main-sequence phase via a disk for a few million years....
RX~J1604.3-2130A is a young, dipper-type, variable star in the Upper Scorpius association, suspected to have an inclined inner disk with respect to its face-on outer disk. We study the eclipses to constrain the inner disk properties.We use time-resolved photometry from the Rapid Eye Mount telescope and Kepler2 data to study the multi-wavelength var...
EX Lup is the prototype of a class of pre-main sequence eruptive stars defined by their repetitive outbursts lasting several months. In 2008 January-September EX Lup underwent its historically largest outburst, brightening by about 4 magnitudes in visual light. In previous studies we discovered on-going silicate crystal formation in the inner disk...
We have monitored nearly a square degree in IC 1396A/Tr 37 over 21 epochs extending over 2014 - 2016 for sources variable in the JHK bands. In our data, 65 +\- 8 % of previously identified cluster members show variations, compared with < 0.3% of field stars. We identify 119 members of Tr 37 on the basis of variability, forming an unbiased sample do...
We have monitored nearly a square degree in IC 1396A/Tr 37 over 21 epochs extending over 2014 - 2016 for sources variable in the JHK bands. In our data, 65 +\- 8 % of previously identified cluster members show variations, compared with < 0.3% of field stars. We identify 119 members of Tr 37 on the basis of variability, forming an unbiased sample do...
Context. IC 1396A is a cometary globule that contains the Class 0 source IC 1396A-PACS-1, which was discovered with Herschel .
Aims. We use IRAM 30m telescope and Gaia DR2 data to explore the star formation history of IC 1396A and investigate the possibilities of triggered star formation.
Methods. IRAM and Herschel continuum data were used to obtai...
Low brightness dips have recently been observed in images of protoplanetary disks, and they are believed to be shadows by the inner disk. We present VLT/SPHERE polarimetric differential imaging of the transition disk around the dipper star RX J1604.3-2130. We gathered 11 epochs that cover a large temporal baseline, to search for variability over ti...
Low brightness dips have been recently observed in images of protoplanetary disks, and they are believed to be shadows by the inner disk. We present VLT/SPHERE polarimetric differential imaging of the transition disk around the dipper star RX J1604.3-2130. We gathered 11 epochs that cover a large temporal baseline, to search for variability over ti...
ASASSN-13db is a M5-type star with a protoplanetary disk, the lowest mass star known to experience accretion outbursts. Since its discovery in 2013, it has experienced two outbursts, the second of which started in November 2014 and lasted until February 2017. We use high- and low-resolution spectroscopy and time-resolved photometry from the ASAS-SN...
ASASSN-13db is a M5-type star with a protoplanetary disk, the lowest mass star known to experience accretion outbursts. Since its discovery in 2013, it has experienced two outbursts, the second of which started in November 2014 and lasted until February 2017. We use high- and low-resolution spectroscopy and time-resolved photometry from the ASAS-SN...
The GW Ori system is a pre-main sequence triple system (GW Ori A/B/C) with companions (GW Ori B/C) at $\sim$1 AU and $\sim$8 AU, respectively, from the primary (GW Ori A). The primary of the system has a mass of 3.9 $M_{\odot}$, but shows a spectral type of G8. Thus, GW Ori A could be a precursor of a B star, but it is still at an earlier evolution...
The GW Ori system is a pre-main sequence triple system (GW Ori A/B/C) with companions (GW Ori B/C) at $\sim$1 AU and $\sim$8 AU, respectively, from the primary (GW Ori A). The primary of the system has a mass of 3.9 $M_{\odot}$, but shows a spectral type of G8. Thus, GW Ori A could be a precursor of a B star, but it is still at an earlier evolution...
We perform a spectroscopic survey of the foreground population in Orion A with MMT/Hectospec. We use these data, along with archival spectroscopic data and photometric data, to derive spectral types, extinction values, and masses for 691 stars. Using the Spitzer Space Telescope data, we characterize the disk properties of these sources. We identify...
We perform a spectroscopic survey of the foreground population in Orion A with MMT/Hectospec. We use these data, along with archival spectroscopic data and photometric data, to derive spectral types, extinction values, and masses for 691 stars. Using the Spitzer Space Telescope data, we characterize the disk properties of these sources. We identify...
The recent progress in instrumentation and telescope development has brought us different ways to observe protoplanetary disks, including interferometers, space missions, adaptive optics, polarimetry, and time- and spectrally-resolved data. While the new facilities have changed the way we can tackle the existing open problems in disk structure and...
Context. Quantifying the gas surface density inside the dust cavities and gaps of transition disks is important to establish their origin. Aims. We seek to constrain the surface density of warm gas in the inner disk of HD 139614, an accreting 9 Myr Herbig Ae star with a (pre-)transition disk exhibiting a dust gap from 2.3 ± 0.1 to 5.3 ± 0.3 AU. Met...
IC1396A is a textbook example of a cometary-shaped bright-rimmed cloud at the edge of the HII region that surrounds the young Tr37 cluster. After more than 40 years of studies in the optical and IR, and many young stars found within the globule, a proof of triggering by the expanding ionization front remained elusive. And then Herschel came. Our He...
HD 142527A is one of the most studied Herbig Ae/Be stars with a transitional
disk, as it has the largest imaged gap in any protoplanetary disk: the gas is
cleared from 30 to 90 AU. The HD 142527 system is also unique in that it has a
stellar companion with a small mass compared to the mass of the primary star.
This factor of $\approx20$ in mass rat...
Filaments represent a key structure during the early stages of the star
formation process. Simulations show filamentary structure commonly formed
before and during the formation of cores. Aims. The Serpens Core represents an
ideal laboratory to test the state-of-the-art of simulations of turbulent Giant
Molecular Clouds. We use Herschel observation...
(Abridged) We use Herschel PACS observations at 70 and 160$\mu$m to probe the
protoplanetary disks around young stars in the CepOB2 clusters Tr37 and NGC7160
and to trace the small-scale cloud structure. We detect 95 protoplanetary disks
at 70$\mu$m, 41 at 160$\mu$m, and obtain upper limits for over 130 objects. The
detection fraction at 70$\mu$m d...
We report the detection of a faint pointlike feature possibly related to
ongoing planet-formation in the disk of the transition disk star HD 169142. The
pointlike feature has a $\Delta$mag(L)$\sim$6.4, at a separation of $\sim$0.11"
and PA$\sim$0$^{\circ}$. Given its lack of an H or K$_{S}$ counterpart despite
its relative brightness, this candidat...
(abridged) We study the young stellar system GW Ori, concentrating on its
accretion/wind activity by using our high-resolution optical spectra and
$U$-band photometry. We also characterize the disk properties of GW Ori by
modeling its spectral energy distribution (SED). By comparing our data to the
synthetical spectra, we classify GW Ori as a G8 st...
We study the photometric variability of a pre-main sequence star (K6,
0.9M⊙) CHXR 20. We test several scenarios for the
variability including variable accretion, variable extinction, cool and
hot spots on the stellar surface and the presence of a potential
companion.
We discuss ASASSN-13db, an EX Lupi-type ("EXor") accretion event on the young stellar object (YSO) SDSS J051011.01–032826.2 (hereafter SDSSJ0510) discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN). Using archival photometric data of SDSSJ0510 we construct a pre-outburst spectral energy distribution and find that it is consistent wi...
The IC1396A globule in the young cluster Tr37, hosting many young stars and
protostars, is assumed to be a site of triggered star formation. We mapped
IC1396A with Herschel/PACS at 70 and 160 micron. The Herschel maps trace in
great detail the very embedded protostellar objects and the structure of the
cloud. PACS data reveal a previously unknown C...
EX Lup-type objects (EXors) are low-mass pre-main sequence objects
characterized by outbursts attributed to highly enhanced disk accretion. The
trigger mechanism of EXor outbursts is still debated. One theory requires a
close (sub)stellar companion that perturbs the inner disk and triggers the
onset of the outburst. Here, we study the radial veloci...
We present a study of accretion and protoplanetary disks around M-type stars
in the 4 Myr-old cluster Tr37. With a well-studied solar-type population, Tr37
is a benchmark for disk evolution. We used low-resolution spectroscopy to
identify 141 members (78 new) and 64 probable members, mostly M-type stars.
H\alpha\ emission provides information about...
We combine newly obtained spectroscopic data from Hectospec and
Hectochelle with photometric data from Paper I (Fang et al., 2009, Cat.
J/A+A/504/461).
The intermediate-resolution spectra of sources were taken with the
Hectospec multi-object spectrograph in the range 3700-9000Å with a
resolution of ~5Å. The observational data were taken on the nig...
We investigate the young stellar objects (YSOs) in the Lynds 1641
(L1641) cloud using multi-wavelength data including Spitzer, WISE,
2MASS, and XMM covering 1390 YSOs across a range of evolutionary
stages. In addition, we targeted a sub-sample of YSOs for optical
spectroscopy with the MMT/Hectospec and the MMT/Hectochelle. We use this
data, along w...
We investigate the young stellar objects (YSOs) in the Lynds 1641 (L1641) cloud using multi-wavelength data including Spitzer, WISE, the Two Micron All Sky Survey, and XMM covering ~1390 YSOs across a range of evolutionary stages. In addition, we targeted a sub-sample of YSOs for optical spectroscopy with the MMT/Hectospec and the MMT/Hectochelle....
Characterization of the properties of young brown dwarfs are important to
constraining the formation of objects at the extreme low-mass end of the IMF.
While young brown dwarfs share many properties with solar-mass T Tauri stars,
differences may be used as tests of how the physics of accretion/outflow and
disk chemistry/dissipation depend on the ma...
The coexistence of fast and slowly rotating cool stars in ZAMS clusters - forming distinct sequences in the color vs. rotation period plane - is providing clues to differences in their pre main-sequence angular momentum evolution. This Cool Stars 17 splinter was dedicated to a discussion of new observational and theoretical results that may help di...
Context. The nearby young stellar association ɛ Cha has an
estimated age of 3-5 Myr, making it an ideal laboratory to study the
disk dissipation process and provide empirical constraints on the
timescale of planet formation. Aims: We wish to complement
existing optical and near-infrared data of the ɛ Cha
association, which provide the stellar prope...
Giant HII regions represent the dominant model of star formation (SF) in
the Galaxy, and the Cepheus Loop is an excellent nearby prototype for
giant, asymmetric HII bubbles. We propose a Spitzer/IRAC mosaic of the
rich and compact principal ionizing cluster Be59 and its parental cloud.
These Spitzer data in conjunction with our X-ray, archival IR,...
The CrA region and the Coronet cluster form a nearby (138 pc), young (1-2
Myr) star-forming region hosting a moderate population of YSO. We present
Herschel PACS photometry at 100 and 160 micron, obtained as part of the
Herschel Gould Belt Survey. The Herschel maps reveal the cluster members with
high sensitivity and high dynamic range. Many of the...
The observations were performed from 1999 February to 2003 November with
the Wide Field Planetary Camera 2 (WFPC2) of the HST using the F606W
(V), F656N (Hα) and F814W (I) filters.
(2 data files).
(abridge) The nearby young stellar association Epsilon Cha association has an
estimated age of 3-5 Myr, making it an ideal laboratory to study the disk
dissipation process and provide empirical constraints on the timescale of
planet formation. We combine the available literature data with our Spitzer IRS
spectroscopy and VLT/VISIR imaging data. The...
Rich young stellar clusters produce HII regions whose expansion into the
nearby molecular cloud is thought to trigger the formation of new stars.
However, the importance of this mode of star formation is uncertain. This
investigation seeks to quantify triggered star formation (TSF) in IC 1396A
(a.k.a., the Elephant Trunk Nebula), a bright rimmed cl...
We explore the accretion mechanisms in EX Lupi, prototype of EXor variables,
during its quiescence and outburst phases. We analyse high-resolution optical
spectra taken before, during, and after its 2008 outburst. In quiescence and
outburst, the star presents many permitted emission lines, including typical
CTTS lines and numerous neutral and ioniz...
With the uniquely high contrast within 0.1" (\Delta mag(L') = 5-6.5
magnitudes) available using Sparse Aperture Masking (SAM) with NACO at VLT, we
detected asymmetry in the flux from the Herbig Fe star HD 142527 with a
barycenter emission situated at a projected separation of 88+/-5 mas
(12.8+/-1.5 AU at 145 pc) and flux ratios in H, K, and L' of 0...
We show that the very young brown dwarf candidate ISO217 (M6.25) is driving
an intrinsically asymmetric bipolar outflow with a stronger and slightly faster
red-shifted component based on spectro-astrometry of forbidden [SII] emission
lines observed in UVES/VLT spectra taken in 2009. ISO217 is only one of a
handful of brown dwarfs and VLMS (M5-M8) f...
Fomalhaut is a young, nearby star that is suspected to harbor an infant
planetary system, interspersed with one or more belts of dusty debris. We
present far-infrared images obtained with the Herschel Space Observatory with
an angular resolution between 5.7 and 36.7 arcsec at wavelengths between 70 and
500 micrometer. The images show the main debri...
The Coronet cluster is a young (1-2 Myr) star-forming region with a few
intermediate-mass stars and a moderate low-mass population, concentrated
in a cloud about 0.7 pc in radius. Despite its compactness,
Herschel/PACS observations, together with ground-based spectroscopy and
Spitzer data, reveal that the region contains objects in very different
s...
We use infrared data from the 2MASS and Spitzer GLIMPSE surveys,
complemented with our own deep Spitzer imaging of the central regions of
Pismis 24, in combination with X-ray data to search for young stellar
objects (YSOs) in NGC 6357 complex. The infrared data constrain the disk
presence and are complemented by optical photometric and spectroscopi...
(abridged) We investigate the properties of young stars and their disks in
the NGC 6357 complex, concentrating on the most massive star cluster within the
complex: Pismis 24. We discover two new young clusters in the NGC 6357 complex.
We give a revised distance estimate for Pismis 24 of 1.7+-0.2 kpc. We find that
the massive star Pis 24-18 is a bin...
EX Lup is the prototype of the EXor class of eruptive young stars. These objects show optical outbursts which are thought to be related to runaway accretion onto the star. In a previous study we observed in situ crystal formation in the disk of EX Lup during its latest outburst in 2008, making the object an ideal laboratory to investigate circumste...
We present a multiwavelength study of three star-forming regions, spanning the age range 1–14 Myr, located between the 30
Doradus complex and supernova SN 1987A in the Large Magellanic Cloud (LMC). We reliably identify about 1000 pre-main-sequence
(PMS) star candidates actively undergoing mass accretion and estimate their stellar properties and mas...
We present Spitzer/IRS spectra of 31 TTS and IRAM/1.3mm observations for 34
low- and intermediate-mass stars in the Cep OB2 region. Including our
previously published data, we analyze 56 TTS and the 3 intermediate-mass stars
with silicate features in Tr 37 (~4 Myr) and NGC 7160 (~12 Myr). The silicate
emission features are well reproduced with a mi...
We describe Spitzer Infrared Spectrograph spectroscopic observations of the ~10 Myr old star, EF Cha. Compositional modeling of the spectra from 5 mum to 35 mum confirms that it is surrounded by a luminous debris disk with LD /L sstarf ~ 10-3, containing dust with temperatures between 225 K and 430 K, characteristic of the terrestrial zone. The EF...
We present new optical spectroscopy with FLAMES/VLT, near-IR imaging with
HAWK-I/VLT, and 870 micron mapping with APEX/LABOCA of the Coronet cluster. The
optical data allow to estimate spectral types, extinction and the presence of
accretion in 6 more M-type members, in addition to the 12 that we had
previously studied. The submillimeter maps and n...
EX Lup is the prototype of the EXor class of young eruptive stars: objects
showing repetitive brightenings due to increased accretion from the
circumstellar disk to the star. In this paper, we report on medium-resolution
near-infrared spectroscopy of EX\,Lup taken during its extreme outburst in
2008, as well as numerical modeling with the aim of de...
We present Spitzer 3.6-24 μm photometry and spectroscopy for stars in the 1-3 Myr old Coronet Cluster, expanding upon the survey of Sicilia-Aguilar et al. Using sophisticated radiative transfer models, we analyze these new data and those from Sicilia-Aguilar et al. to identify disks with evidence for substantial dust evolution consistent with disk...
We describe Spitzer IRS spectroscopic observations of the 10 Myr-old star, EF
Cha. Compositional modeling of the spectra from 5 {\mu}m to 35 {\mu}m confirms
that it is surrounded by a luminous debris disk with LD/L\star ~ 10-3,
containing dust with temperatures between 225 K and 430 K characteristic of the
terrestrial zone. The EF Cha spectrum show...
We present a deep Spitzer/Infrared Array Camera (IRAC) survey of the OB association IC 1795 carried out to investigate the evolution of protoplanetary disks in regions of massive star formation. Combining Spitzer/IRAC data with Chandra/Advanced CCD Imaging Spectrometer observations, we find 289 cluster members. An additional 340 sources with an inf...
We report monitoring observations of the T Tauri star EX Lupi during its outburst in 2008 in the CO fundamental
band at 4.6–5.0 μm. The observations were carried out at the Very Large Telescope and the Subaru Telescope at six
epochs from 2008 April to August, covering the plateau of the outburst and the fading phase to a quiescent state.
The line f...
We present a multi-wavelength study of three star-forming regions,
spanning the age range 1-14 Myrs, located between the 30 Doradus complex
and the supernova SN1987A in the Large Magellanic Cloud (LMC). We use a
novel self-consistent method to reliably identify pre-main sequence
(PMS) objects actively undergoing mass accretion and estimate their
st...
We obtained Herschel PACS and SPIRE images of the thermal emission of the debris disk around the A5V star ò Pic. The disk is well resolved in the PACS filters at 70, 100, and 160 üm. The surface brightness profiles between 70 and 160 üm show no significant asymmetries along the disk, and are compatible with 90% of the emission between 70 a...
We present five band imaging of the Vega debris disc obtained using the
Herschel Space Observatory. These data span a wavelength range of 70-500 um
with full-width half-maximum angular resolutions of 5.6-36.9". The disc is well
resolved in all bands, with the ring structure visible at 70 and 160 um. Radial
profiles of the disc surface brightness ar...
We obtained Herschel PACS and SPIRE images of the thermal emission of the debris disk around the A5V star {\beta} Pic. The disk is well resolved in the PACS filters at 70, 100, and 160 {\mu}m. The surface brightness profiles between 70 and 160 {\mu}m show no significant asymmetries along the disk, and are compatible with 90% of the emission between...
We summarize the first results from the Gould Belt Survey, obtained toward the Aquila rift and Polaris Flare regions during the science demonstration phase of Herschel. Our 70-500 üm images taken in parallel mode with the SPIRE and PACS cameras reveal a wealth of filamentary structure, as well as numerous dense cores embedded in the filaments. B...