All Outputs (156)

DUSTY OB STARS IN THE SMALL MAGELLANIC CLOUD. II. EXTRAGALACTIC DISKS OR EXAMPLES OF THE PLEIADES PHENOMENON? (2013)
Journal Article
Adams, J. J., Simon, J. D., Bolatto, A. D., Sloan, G. C., Sandstrom, K. M., Schmiedeke, A., …Keller, L. D. (2013). DUSTY OB STARS IN THE SMALL MAGELLANIC CLOUD. II. EXTRAGALACTIC DISKS OR EXAMPLES OF THE PLEIADES PHENOMENON?. Astrophysical Journal, 771(2), Article ARTN 112. https://doi.org/10.1088/0004-637x/771/2/112

We use mid-infrared Spitzer spectroscopy and far-infrared Herschel photometry for a sample of 20 main sequence O9–B2 stars in the Small Magellanic Cloud (SMC) with strong 24 μm excesses to investigate the origin of the mid-IR emission. Either debris... Read More about DUSTY OB STARS IN THE SMALL MAGELLANIC CLOUD. II. EXTRAGALACTIC DISKS OR EXAMPLES OF THE PLEIADES PHENOMENON?.

The VMC survey: VII. Reddening map of the 30 Doradus field and the structure of the cold interstellar medium (2013)
Journal Article
Tatton, B. L., van Loon, J. T., Cioni, M., Clementini, G., Emerson, J. P., Girardi, L., …Rubele, S. (2013). The VMC survey: VII. Reddening map of the 30 Doradus field and the structure of the cold interstellar medium. Astronomy & Astrophysics, 554, A33. https://doi.org/10.1051/0004-6361/201321209

Context. The details of how galaxies have evolved over cosmological times are imprinted in their star formation history, chemical enrichment and morpho-kinematic structure. Parameters behind these, such as effective temperature and metallicity, can b... Read More about The VMC survey: VII. Reddening map of the 30 Doradus field and the structure of the cold interstellar medium.

The UK Infrared Telescope M33 monitoring project – III. Feedback from dusty stellar winds in the central square kiloparsec (2013)
Journal Article
Javadi, A., van Loon, J. T., Khosroshahi, H., & Mirtorabi, M. T. (2013). The UK Infrared Telescope M33 monitoring project – III. Feedback from dusty stellar winds in the central square kiloparsec. Monthly Notices of the Royal Astronomical Society, 432(4), 2824-2836. https://doi.org/10.1093/mnras/stt640

We have conducted a near-infrared monitoring campaign at the UK Infrared Telescope, of the Local Group spiral galaxy M33 (Triangulum). The main aim was to identify stars in the very final stage of their evolution, and for which the luminosity is more... Read More about The UK Infrared Telescope M33 monitoring project – III. Feedback from dusty stellar winds in the central square kiloparsec.

The thermal dust emission in N158–N159–N160 (LMC) star-forming complex mapped by Spitzer, Herschel and LABOCA (2013)
Journal Article
Galametz, M., Hony, S., Galliano, F., Madden, S. C., Albrecht, M., Bot, C., …van Loon, J. T. (2013). The thermal dust emission in N158–N159–N160 (LMC) star-forming complex mapped by Spitzer, Herschel and LABOCA. Monthly Notices of the Royal Astronomical Society, 431(2), 1596-1617. https://doi.org/10.1093/mnras/stt280

Low-metallicity galaxies exhibit different properties of the interstellar medium (ISM) compared to nearby spiral galaxies. Obtaining a resolved inventory of the various gas and dust components of massive star-forming regions and diffuse ISM is necess... Read More about The thermal dust emission in N158–N159–N160 (LMC) star-forming complex mapped by Spitzer, Herschel and LABOCA.

The VLT-FLAMES Tarantula Survey: IX. The interstellar medium seen through diffuse interstellar bands and neutral sodium⋆ (2013)
Journal Article
van Loon, J. T., Bailey, M., Tatton, B. L., Maíz Apellániz, J., Crowther, P. A., de Koter, A., …Walborn, N. R. (2013). The VLT-FLAMES Tarantula Survey: IX. The interstellar medium seen through diffuse interstellar bands and neutral sodium⋆. Astronomy & Astrophysics, 550, Article A108. https://doi.org/10.1051/0004-6361/201220210

Context. The Tarantula Nebula (a.k.a. 30 Dor) is a spectacular star-forming region in the Large Magellanic Cloud (LMC), seen through gas in the Galactic disc and halo. Diffuse interstellar bands (DIBs) offer a unique probe of the diffuse, cool-warm g... Read More about The VLT-FLAMES Tarantula Survey: IX. The interstellar medium seen through diffuse interstellar bands and neutral sodium⋆.

The VMC Survey: VI. Quasars behind the Magellanic system⋆ (2012)
Journal Article
Cioni, M. L., Kamath, D., Rubele, S., van Loon, J. T., Wood, P. R., Emerson, J. P., …Ripepi, V. (2013). The VMC Survey: VI. Quasars behind the Magellanic system⋆. Astronomy & Astrophysics, 549, Article A29. https://doi.org/10.1051/0004-6361/201219696

Context. The number and spatial distribution of confirmed quasi-stellar objects (QSOs) behind the Magellanic system is limited. This undermines their use as astrometric reference objects for different types of studies. Aims. We have searched for c... Read More about The VMC Survey: VI. Quasars behind the Magellanic system⋆.

Early-stage young stellar objects in the Small Magellanic Cloud (2012)
Journal Article
Oliveira, J., Th. van Loon, J., Sloan, G., Sewiło, M., Kraemer, K., Wood, P., …Simon, J. (2013). Early-stage young stellar objects in the Small Magellanic Cloud. Monthly Notices of the Royal Astronomical Society, 428(4), 3001-3033. https://doi.org/10.1093/mnras/sts250

We present new observations of 34 YSO candidates in the SMC. The anchor of the analysis is a set of Spitzer-IRS spectra, supplemented by groundbased 3-5 micron spectra, Spitzer and NIR photometry, optical spectroscopy and radio data. The sources' SED... Read More about Early-stage young stellar objects in the Small Magellanic Cloud.

Ice chemistry in massive Young Stellar Objects: the role of metallicity (2011)
Journal Article
Oliveira, J., van Loon, J., Sloan, G., Indebetouw, R., Kemper, F., Tielens, A. G. M., …Meixner, M. (2011). Ice chemistry in massive Young Stellar Objects: the role of metallicity. Monthly Notices of the Royal Astronomical Society: Letters, 411(1), L36–L40. https://doi.org/10.1111/j.1745-3933.2010.00990.x

We present the comparison of the three most important ice constituents (water, CO and CO2) in the envelopes of massive Young Stellar Objects (YSOs), in environments of different metallicities: the Galaxy, the Large Magellanic Cloud (LMC) and, for the... Read More about Ice chemistry in massive Young Stellar Objects: the role of metallicity.

Ice chemistry in embedded young stellar objects in the Large Magellanic Cloud (2009)
Journal Article
Oliveira, J. M., van Loon, J. T., Chen, C. R., Tielens, A. G. G. M., Sloan, G. C., Woods, P. M., …Marengo, M. (2009). Ice chemistry in embedded young stellar objects in the Large Magellanic Cloud. Astrophysical Journal, 707(1269), https://doi.org/10.1088/0004-637X/707/2/1269

We present spectroscopic observations of a sample of 15 embedded young stellar objects (YSOs) in the Large Magellanic Cloud (LMC). These observations were obtained with the Spitzer Infrared Spectrograph (IRS) as part of the SAGE-Spec Legacy program.... Read More about Ice chemistry in embedded young stellar objects in the Large Magellanic Cloud.

Star Formation in the Eagle Nebula and NGC 6611 (2006)
Journal Article
Oliveira, J. M., Jeffries, R. D., & van Loon, J. T. (2006). Star Formation in the Eagle Nebula and NGC 6611. Proceedings of the International Astronomical Union, 2(S237), https://doi.org/10.1017/S1743921307002487

We present IZJHKL' photometry of the core of the cluster NGC 6611 in the Eagle Nebula. This photometry is used to constrain the Initial Mass Function (IMF) and the circumstellar disk frequency of the young stellar objects. Optical spectroscopy of 258... Read More about Star Formation in the Eagle Nebula and NGC 6611.

Circumstellar discs in the young σ Orionis cluster (2006)
Journal Article
Oliveira, J., Jeffries, R., Van Loon, J., & Rushton, M. (2006). Circumstellar discs in the young σ Orionis cluster. Monthly Notices of the Royal Astronomical Society, 369(1), 272 -280. https://doi.org/10.1111/j.1365-2966.2006.10299.x

We present new K- and L'-band imaging observations for members of the young (3-5 Myr) sigma Orionis cluster, obtained with UIST at UKIRT. We determine (K-L') colour excesses with respect to the photospheres, finding evidence for warm circumstellar du... Read More about Circumstellar discs in the young σ Orionis cluster.

Young stars and their circumstellar disks in the Sigma Orionis cluster (2004)
Conference Proceeding
M. Oliveira, J., D. Jeffries, R., Th. van Loon, J., & J. Kenyon, M. (2004). Young stars and their circumstellar disks in the Sigma Orionis cluster. In Open Issues in Local Star Formation (55–62). https://doi.org/10.1007/1-4020-2600-5_6

The sigma Orionis cluster is a young association evolving under the disruptive influence of its massive O-star namesake. We are analysing this cluster as part of a program to characterise the influence of O-stars on the early stages of stellar evolut... Read More about Young stars and their circumstellar disks in the Sigma Orionis cluster.

Mid-infrared observations of young stellar objects in the vicinity of sigma Orionis (2004)
Journal Article
Oliveira, J. M., & van Loon, J. T. (2004). Mid-infrared observations of young stellar objects in the vicinity of sigma Orionis. Astronomy & Astrophysics, 418(2), https://doi.org/10.1051/0004-6361%3A20034518

We present new mid-infrared observations of objects in the vicinity of the O-star sigma Orionis, obtained with TIMMI-2 at ESO. By constraining their near- and mid-infrared spectral energy distributions, we established the nature of previously known I... Read More about Mid-infrared observations of young stellar objects in the vicinity of sigma Orionis.

The kinematics and physical properties for some H II regions to the North-East of NGC 4945**
Presentation / Conference
Van Loon. The kinematics and physical properties for some H II regions to the North-East of NGC 4945**. Presented at 3rd International Scientific Conference of Alkafeel University (ISCKU 2021)

We study the ionized outflows to the North-East of the edge-on spiral galaxy NGC 4945 with the combination of the Fabry-Perot (FP) and long-slit (LS) observations at the South African Large Telescope (SALT). The FP observation was used to analyse Ha... Read More about The kinematics and physical properties for some H II regions to the North-East of NGC 4945**.

The Role of AGB Stars Feedback in Sustaining Galaxy Evolution
Journal Article
Javadi, A., Van Loon, J., & Khosroshahi, H. The Role of AGB Stars Feedback in Sustaining Galaxy Evolution. arXiv, https://doi.org/10.48550/arXiv.1610.00254

We have conducted a near-infrared monitoring campaign at the UK InfraRed Telescope, of the Local Group spiral galaxy M33. The main aim was to identify stars in the very final stage of their evolution, and for which the luminosity is more directly rel... Read More about The Role of AGB Stars Feedback in Sustaining Galaxy Evolution.

The curious case of Betelgeuse
Conference Proceeding
van Loon, J. T. (2023). The curious case of Betelgeuse. In The Sixteenth Marcel Grossmann Meeting On Recent Developments in Theoretical and Experimental General Relativity, Astrophysics, and Relativistic Field Theories (In 4 Volumes). https://doi.org/10.1142/9789811269776_0289

Betelgeuse is the nearest red supergiant, one of the brightest stars in our sky, and statistically speaking it would be expected to be “typical”. Yet it exhibits many features that seem “curious”, to say the least. For instance it has a high proper m... Read More about The curious case of Betelgeuse.