Browsing University of Hertfordshire by Author "Froebrich, Dirk"

Now showing items 1-6 of 6

    • The excitation mechanisms and evolutionary stages of UWISH2 planetary nebula candidates 

      Jones, Alex; Gledhill, Timothy; Froebrich, Dirk; Smith, Michael (2018-10-01)
      We present medium-resolution K-band long-slit spectroscopy of 29 true, likely, possible, and candidate Galactic Plane planetary nebulae (PNe) from the UWISH 2 survey, many of which have only been recently discovered. These ...

    • FSR 1716: A new Milky Way Globular Cluster confirmed using VVV RR Lyrae stars 

      Minniti, Dante; Palma, Tali; Dékány, Istvan; Hempel, Maren; Rejkuba, Marina; Pullen, Joyce; Alonso-García, Javier; Barbá, Rodolfo; Barbuy, Beatriz; Bica, Eduardo; Bonatto, Charles; Borissova, Jura; Catelan, Marcio; Carballo-Bello, Julio A.; Chene, Andre Nicolas; Clariá, Juan J.; Cohen, Roger E.; Contreras-Ramos, Rodrigo; Dias, Bruno; Emerson, Jim; Froebrich, Dirk; Buckner, Anne S. M.; Geisler, Douglas; Gonzalez, Oscar A.; Gran, Felipe; Hagdu, Gergely; Irwin, Mike; Ivanov, Valentin D.; Kurtev, Radostin; Lucas, Philip W.; Majaess, Daniel; Mauro, Francesco; Moni-Bidin, Christian; Navarrete, Camila; Alegría, Sebastian Ramírez; Saito, Roberto K.; Valenti, Elena; Zoccali, Manuela (2017-03-24)
      We use deep multi-epoch near-IR images of the VISTA Variables in the V\'ia L\'actea (VVV) Survey to search for RR Lyrae stars towards the Southern Galactic plane. Here we report the discovery of a group of RR Lyrae stars ...

    • Photometric variability of massive young stellar objects 

      Teixeira, G. D. C.; Kumar, M. S. N.; Smith, L.; Lucas, P. W.; Morris, C.; Borissova, J.; Monteiro, M. J. P. F. G.; Garatti, A. Caratti o; Peña, C. Contreras; Froebrich, Dirk; Gameiro, J. F. (2018-11-05)
      The Vista Variables in the Via Lactea (VVV) survey has allowed for an unprecedented number of multi-epoch observations of the southern Galactic plane. In a recent paper, 13 massive young stellar objects (MYSOs) have already ...

    • Planetary Nebulae in the UWISH2 survey 

      Gledhill, Timothy; Froebrich, Dirk; Campbell-White, J.; Jones, Alex (2018-09-21)
      Near-infrared imaging in the 1 - 0 S(1) emission line of molecular hydrogen is able to detect planetary nebulae (PNe) that are hidden from optical emission line surveys.We present images of 307 objects from the UWISH2 ...

    • Short and long term near-infrared spectroscopic variability of eruptive protostars from VVV 

      Guo, Zhen; Lucas, P. W.; Peña, C. Contreras; Kurtev, R. G.; Smith, L. C.; Borissova, J.; Alonso-García, J.; Minniti, D.; Garatti, A. Caratti o; Froebrich, Dirk (2020-02-01)
      Numerous eruptive variable young stellar objects (YSOs), mostly Class I systems, were recently detected by the near-infrared Vista Variables in the Via Lactea (VVV) survey. We present an exploratory near-infrared spectroscopic ...

    • A survey for variable young stars with small telescopes – IX. Evolution of spot properties on YSOs in IC 5070 

      Herbert, Carys; Froebrich, Dirk; Vanaverbeke, Siegfried; Scholz, Aleks; Eislöffel, Jochen; Urtly, Thomas; Walton, Ivan L; Wiersema, Klaas; Quinn, Nick J; Piehler, Georg; Aimar, Mario Morales; García, Rafael Castillo; Vanmunster, Tonny; Alfaro, Francisco C Soldán; de la Cuesta, Faustino García; Licchelli, Domenico; Perez, Alex Escartin; Mañanes, Esteban Fernández; Ribes, Noelia Graciá; González, José Luis Salto; Futcher, Stephen R L; Nelson, Tim; Dvorak, Shawn; Moździerski, Dawid; Kotysz, Krzysztof; Mikołajczyk, Przemysław; Fleming, George; Phillips, Mark; Vale, Tony; Dubois, Franky; Eggenstein, Heinz-Bernd; Heald, Michael A; Lewin, Pablo; OKeeffe, Derek; Popowicz, Adam; Bernacki, Krzysztof; Malcher, Andrzej; Lasota, Slawomir; Fiolka, Jerzy; Dustor, Adam; Percy, Stephen C; Devine, Pat; Patel, Aashini L; Dickers, Matthew D; Dover, Lord; Grozdanova, Ivana I; Urquhart, James S; Lynch, Chris J R (2024-04-01)
      We present spot properties on 32 periodic young stellar objects in IC 5070. Long term, ∼5 yr, light curves in the V, R, and I-bands are obtained through the HOYS (Hunting Outbursting Young Stars) citizen science project. ...