All Outputs (170)

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.

Circumstellar discs around solar-mass stars in NGC 6611 (2005)
Journal Article
Oliveira, J., Jeffries, R., Th. van Loon, J., Littlefair, S., & Naylor, T. (2005). Circumstellar discs around solar-mass stars in NGC 6611. Monthly Notices of the Royal Astronomical Society: Letters, 358(1), L21-L24. https://doi.org/10.1111/j.1745-3933.2005.00020.x

We have performed IZJHKL' observations in NGC 6611, the young cluster that ionises the Eagle Nebula. We have discovered a rich pre-main sequence concentrated around the O-stars in the cluster. As measured by their L'-band excesses, at least 58% +/- 5... Read More about Circumstellar discs around solar-mass stars in NGC 6611.

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.

An L'-band survey for circumstellar discs around low-mass stars in the young σ Orionis cluster (2004)
Journal Article
Jeffries, R., Oliveira, J., & Van Loon, J. (2004). An L'-band survey for circumstellar discs around low-mass stars in the young σ Orionis cluster. Monthly Notices of the Royal Astronomical Society, 347(4), 1327 -1336. https://doi.org/10.1111/j.1365-2966.2004.07315.x

We present new K- and L'-band imaging of a representative sample of members of the young 3-5 Myr old sigma Orionis cluster. We identified objects with (K-L') excess by analysing colour-colour diagrams and comparing the observations with empirical mai... Read More about An L'-band survey for circumstellar discs around low-mass stars in the young σ Orionis cluster.

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.