HETH science

Our main interest is the study of (massive) stellar explosions, their environments and hosts.

Christmas Burst

Gamma-ray burstsStrange GRBs and GRB-supernovae

Gamma-ray bursts are some of the most luminous explosions in the Universe. They are divided in long and short GRBs possibly reflecting two different progenitor types (death of a massive star vs. coalescence of two compact objects). Despite two decades of afterglow observations many mysteries still remain. HETH has designated ToO programs at different telescopes to follow GRB afterglows (e.g. GTC, OSN, ALMA and PdB). HETH people are also member of the European X-shooter collaboration on GRBs.

At HETH we study GRBs across all wavelengths from X-ray to radio. We focus on peculiar events such as the famous "Christmas Burst", GRB 101225A. The afterglow of this peculiar GRB showed mostly thermal emission in contrast to the usual power-law behaviour and we interpreted it as a merger system where, in the final GRB, the jet interacted with a thick shell ejected some years before the GRB.

Along with their prompt emission powered by jets, GRBs also produce a special kind of supernova explosions, called "broad-lined type Ic". These stellar explosions contain neither hydrogen nor helium, and the ejecta expands at very high speeds, typically 10% of light speed. Recently, a link has also been established between GRBs and superluminous SNe for GRB 111209A/SN 2011kl (see also Kann et al. 2016). At HETH we have a dedicated observing program to follow-up these SNe with the GTC.

In August 2017, much earlier than ever expected, the first simultaneous detection of a gravitational wave source coming from a binary neutron star merger and a short GRB had been possible. This confirmed many models both on NS-NS mergers and of the progenitors of short GRBs. At HETH we were and are part of several large collaborations to study these events at all wavelengths. For the next LIGO run we are part of the ENGRAVE consortium at ESO and several other large efforts.

Press release on GW/GRB 170817A.


SupernovaeExtreme events and outliers

Supernovae come in many different flavours and most (except SNe Ia) are related to the death of a more or less massive star. At HETH we are predominantly interested in SNe IIn (narrow lines from interaction with circumstellar material), superluminous supernovae and broad-line SNe Ic. HETH has several ongoing observing programs at GTC, OSN and CAHA.

Once again, we like the odd and exceptional events such as the impostor/SN IIn SN 2015bh, a possible analogue of SN 2009ip. This possible SN showed a series of outbursts varying by about 2 mag over at least 21 years and at a position in the HR diagram similar to the events of Eta Carina, albeit at lower luminosities. In 2015 it experienced first a larger "precursor" and then the more luminous "main event" whose lightcurve resembled a normal SN IIn but with a total luminosity on the edge of a real core-collapse event. The spectra clearly showed the traces of previous larger ejections of material. The late time behaviour of this event and SN 2009ip let us speculate that the star might not have exploded but is on the way to become a Wolf-Rayet star after shedding its outer envelope.

Press release on SN 2015bh


Hosts GRBs hosts near and far, SN hosts and explosion sites

Thanks to their high luminosity, GRBs can be used as lighthouses to study the ISM in their host galaxies up to very high redshifts. The ISM imprints absorption lines onto the smooth afterglow continuum. Medium to high resolution spectra are especially suited for this purpose: Study the kinematics of the ISM by identifying several components, observe line variability to infer distances (usually fine-structure lines, but also varying HI asbsorpion has been observed in Thöne et al. 2011), study the chemical abundances and trace the metallicity evolution and infer extinction properties in the line-of-sight. Within the European X-shooter collaboration, HETH members are working on various sample papers using more than 70 spectra collected by X-shooter since 2009.

Furthermore, at HETH we study host properties by observing them directly in emission. GRB hosts are thought to be a population of young, blue and star-forming galaxies, often subluminous, in particular at low redshift while SLSN hosts are probably even more extreme galaxies (see e.g. Thöne et al. 2015). HETH people are members of the SHOALS and SUSHIES (SLSN host galaxies) collaborations to study GRB and SLSN hosts.

Another main interest of HETH is the detailed study of nearby GRB and SN environment using IFU spectroscopy and other resolved techniques such as narrow-band tuneable filters (at OSIRIS/GTC). The hosts of GRB 060505 (Thöne et al. 2015) and GRB 100316D (Izzo et al. 2017) are two out of only three GRB hosts so far studied with 3D spectra and we are part of several collaborations to study a larger sample of hosts with resolved techniques. Izzo et al. 2018 recently published a resolved study on the SLSN Type I SN 2017egmin a seemingly solar metallicity host, where the SLSN originated in an underlying, metal-poor and young stellar population.


NovaeNovae as lithium farms, Nova shells in 3D

The progenitors of classical novae are white dwarfs in tight binary systems which accrete matter from a companion star and gas piles up on its surface. Once the pressure and temperature at the base of the layer reaches a critical value, thermonuclear reactions ignite the gas. Novae have been observed for over 100 years, but new instruments are revealing important details behind the emisson mechanisms as well as the geometry of the ejecta.

High-resolution spectrograph lead to the discovery of lithium during the early nova phase (Izzo et al. 2015) This has important consequences for the chemical enrichment of Li in the Galaxy: observations of young stellar populations show an over-abundance of Li in their spectra, whose origin is still unclear. The detection of Li and Be in V5668 Sgr (Molaro et al. 2016) which decays into lithium after 56 days, suggests that classical novae represent the main farms of lithium in the Galaxy. Izzo et al. 2018 have now also detected Be in a fast nova, adding this class to the sources of Li in the Galaxy.
We furthermore use IFU data to study the asphericity and kinematics in nova shells, i.e. at very late phases. The match with archival data from ESO-VLT and the Hubble Space Telescope, as well as the use of incoming GAIA data, is funamental to study a reliable use of novae as local distance indicators and as possible progenitors of Supernovae Ia.

Press release on novae as Li factories


Cosmology Cosmology with SNe and GRBs

GRB-SNe have a luminosity-stretch relationship (Cano et al. 2014) that is analogous to the luminosity-decline relationship measured for SNe Ia. The latter has been succesfully used to demonstrate the existance of Dark Energy, which culminated in being awarded the Nobel Prize in Physics in 2011. While the field of GRB-SN-cosmology is still in its infancy, it has already been demonstrated that GRB-SN can also be used to constrain the Hubble constant (Cano, Jakobsson & Geirsson 2014) and the mass and energy density of the cosmos (Li, Hjorth & Wojtak 2014) . Additional studies are ongoing to reduce the amount of scatter in Hubble diagrams of GRB-SN and enhance their role as cosmological probes.

Using SNe Ia for cosmology is currently limited to redshifts around z~1.5-2, hence we have little information about the era when the first starts and galaxies formed and the initial large-scale structures begun to cluster. GRBs are a unique probe for this "dark" era since they have been observed out to redshifts of nearly 10 (the current record is GRB 090429B at z = 9.4).
At HETH we study how to use GRBs as distance indicators up to these high redshifts. Recently a correlation has been proposed (Izzo et al. 2015), that has a tight data scatter and intrinsically links prompt and afterglow quantities. The study of large datasets of GRB, coupled with advanced analysis techniques, will allow us to measure accurately the evolution history at very large redshifts and obtain information about the nature of the Dark Energy.


GRBspec A public database for GRB afterglow spectra

GRBspec is a database that collects spectroscopy of gamma-ray burst, afterglows, their associated supernovae and their host galaxies. It includes GRB information (duration, energetics, redshifts, etc.), the spectroscopic data, such as 1D and 2D data with their associated error frames, and the associated measurements to the spectra (equivalent widths, column densities, or line fluxes). GRBspec is currently the largest database of its kind in the world and it keeps growing through the work of HETH and the contribution of other scientists from around the world.

Link to GRBspec

The project is supported by a 2016 BBVA Foundation Grant for Researchers and Cultural Creators.



Many of the advances in research come hand in hand with technological developments. HETH has been leading a feasibility study and the conceptual design phase of OCTOCAM, an instrument concept developed at IAA since 2009, and participates in the science teams of HiPERCAM at the 10.4m GTC (La Palma, Spain), and SOXS at the 3.6m NTT (La Silla, Chile).

OCTOCAM will be the next facility instrument of the 8.1m Gemini South telescope, in Chile. It is an 8-channel imager and spectrograph, simultaneously imaging a field of view of 3’x3’ in g'r'i'z'YJH and K bands, or obtaining long slit spectroscopy with R=4000 between 3700 and 23500 Å. State-of-the-art detectors allow observations with high time resolution, opening a window in the wavelength range - spectral resolution - temporal resolution diagram not covered by any other instrument until now. Its main science goal is the study of transients and is specifically thought as LSST follow-up instrument.
Until Dec. 2017, OCTOCAM was lead by the HETH group with Antonio de Ugarte Postigo as PI and Christina Thöne as PM Spain in collaboration with Southwest Research Institute, George Washington University and FRACTAL S.L.N.E. On Dec. 5, 2017, SwRI decided to terminate the subcontract with IAA "for convenience" to take full control of the development of the instrument after tedious discussions and psychological warfare.
OCTOCAM at Gemini webpage     IAA press release

HETH is currently proposing a new workhorse instrument for GTC, which has recently issued a call for a second generation instrument (link to the call) .
The first concept will be presented at the "VI Science with the GTC" meeting in Valencia in Dec. 2018. Stay tuned!

HETH People

HETH was founded in 2012 and is not only a young group but is also composed of young researchers. And we are probably the most international group at IAA.


HETH in September 2018
(with visitors O. Nentvich and R. Martone)

  • Christina Thöne, Ramón y Cajal fellow, group leader   (cthoene at iaa.es)
  • Antonio de Ugarte Postigo, Ramón y Cajal fellow, co-PI   (deugarte at iaa.es) personal HP
  • Luca Izzo, postdoc   (izzo at iaa.es) personal HP
  • Alexander Kann, Juan de la Cierva fellow   (kann at iaa.es)
  • Martin Blazek, PTA (alf at iaa.es) personal HP
  • Kasia Bensch, PhD student   (kasia at iaa.es)

  • Former members:
  • Rubén Sánchez-Ramírez   now postdoc at INAF, Rome
  • Ana Sagues Carracedo   now PhD student at AlbaNova, Stockholm
  • Zach Cano   left astronomy

  • In memoriam Javier Gorosabel (27.10.1969 - 21.4.2015)


Recent publications and highlights. A full publication list can be found in this ADS repository

Press releases


  • The luminous host galaxy, faint supernova and rapid afterglow rebrightening of GRB 100418A
    de Ugarte Postigo, A.; Thoene, C. C.; Bensch, K.; van der Horst, A. J.; Kann, D. A.; Cano, Z.; Izzo, L. et al., A&A in press, arXiv:1807.04281
  • X-shooter and ALMA spectroscopy of GRB 161023A - A study of metals and molecules in the line-of-sight towards a luminous GRB
    de Ugarte Postigo, A.; Thöne, C. C.; Bolmer, J.; Schulze, S.; Martín, S.; Kann, D. A. et al. (other coauthors: Izzo, L.. Bensch, K.; Cano, Z.) A&A in press, arXiv:1806.07393
  • The X-shooter GRB afterglow legacy sample (XS-GRB)
    Selsing, J., Malesani, D., Goldoni, P., Fynbo, J. P. U., Krühler, T. et al. (coauthors Cano, Z., de Ugarte Postigo, A., Kann, D. A., Thöne, C. C.), A&A submitted, arXiv:1802.07727
  • The optical afterglow of the short gamma-ray burst associated with GW170817
    Lyman, J. D.; Lamb, G. P.; Levan, A. J.; Mandel, I.; Tanvir, N. R. (coauthors Cano, Z., Izzo, L., Thöne, C. C., de Ugarte Postigo, A.), NatAs in press, arXiv:1801.02669
  • Beryllium detection in the very fast nova ASASSN-16kt (V407 Lupi)
    Izzo, L.; Molaro, P.; Bonifacio, P.; Della Valle, M.; Cano, Z.; de Ugarte Postigo, A.; Prieto, J. L.; Thöne, C.; Vanzi, L.; Zapata, A.; Fernandez, D., 2018, MNRAS, 478, 1601
  • The host of the Type I SLSN 2017egm: A young, sub-solar metallicity environment in a massive spiral galaxy
    Izzo, L.; Thöne, C. C.; García-Benito, R.; de Ugarte Postigo, A.; Cano, Z.; Kann, D. A.; Bensch, K.; Galadí-Enríquez, D.; Hedrosa, R. P.; Della Valle, M., 2018, A&A, 610, id.A11
  • A spectroscopic look at the gravitationally lensed type Ia SN 2016geu at z=0.409
    Cano, Z.; Selsing, J.; Hjorth, J.; de Ugarte Postigo, A.; Christensen, L.; Gall, C.; Kann, D. A., 2018, MNRAS, 473, 4257
  • Cosmic evolution and metal aversion in super-luminous supernova host galaxies
    Schulze, S., Krühler, T., Leloudas, G. et al. (coauthors de Ugarte Postigo, A., Thöne, C.), 2018, MNRAS, 473,1258
  • The MUSE view of the host galaxy of GRB 100316D
    Izzo, L., Thöne, C., Schulze S. et al. 2017, MNRAS 472, 4480
  • ALMA and GMRT Constraints on the Off-axis Gamma-Ray Burst 170817A from the Binary Neutron Star Merger GW170817
    Kim, S.; Schulze, S.; Resmi, L.; González-López, J.; Higgins, A. B. (coauthors de Ugarte Postigo, A.; Kann, D. A.; Cano, Z.; Sánchez-Ramírez, R.; Thöne, C. C.) 2017, ApJL 850, id. L21
  • The Environment of the Binary Neutron Star Merger GW170817
    Levan, A. J.; Lyman, J. D.; Tanvir, N. R.; Hjorth, J.; Mandel, I. (coauthors Cano, Z., Izzo, L., Thöne C. C., de Ugarte Postigo, A. 2017, ApJL, 848, id. L28
  • The Emergence of a Lanthanide-rich Kilonova Following the Merger of Two Neutron Stars
    Tanvir, N. R.; Levan, A. J.; González-Fernández, C.; Korobkin, O.; Mandel, I. (coauthors Cano, Z., Kann, D. A., Thöne C. C., de Ugarte Postigo, A.) 2017, ApJL 848L, id. L27
  • Multi-messenger Observations of a Binary Neutron Star Merger
    Abbott, B. P.; Abbott, R.; Abbott, T. D.; Acernese, F.; Ackley, K. (coauthors Cano, Z., Izzo, L., Kann, D. A., Thöne C. C., de Ugarte Postigo, A.) 2017, ApJL, 848, id. L12
  • GRB 161219B / SN 2016jca: A low-redshift gamma-ray burst supernova powered by radioactive heating
    Cano, Z.; Izzo, L.; de Ugarte Postigo, A.; Thoene, C. C.; Kruehler, T. et al. (coauthors Kann, D. A.; Sánchez-Ramírez, R.) 2017, A&A 605, 107
  • The Optical/NIR afterglow of GRB 111209A: Complex yet not Unprecedented
    Kann, D. A.; Schady, P.; Olivares E., F.; Klose, S.; Rossi, A. et al., A&A subm. arXiv:1706.00601
  • SN 2015bh: NGC 2770's 4th supernova or a luminous blue variable on its way to a Wolf-Rayet star?
    Thöne, C. C.; de Ugarte Postigo, A.; Leloudas, G., Gall, C.; Cano, Z. et al., 2017, A&A 599, A129
  • GRB 110715A: the peculiar multiwavelength evolution of the first afterglow detected by ALMA
    Sánchez-Ramírez, R.; Hancock, P. J.; Jóhannesson, G. et al. (coauthors de Ugarte Postigo, A., Thöne, C. C., Gorosabel, J.), 2017, MNRAS, 464, Issue, 4624
  • The Observer's Guide to the Gamma-Ray Burst-Supernova Connection
    Cano, Z., Wang, S.-Q., Dai, Z.-G., & Wu, X.-F. 2017, Advances in Astronomy, 2017, 8929054
  • Highly Luminous Supernovae associated with Gamma-Ray Bursts I.: GRB 111209A/SN 2011kl in the Context of Stripped-Envelope and Superluminous Supernovae
    Kann, D. A.; Schady, P.; Olivares E., F.; Klose, S.; Rossi, A. et al. A&A in press, arXiv:1606.06791
  • The superluminous transient ASASSN-15lh as a tidal disruption event from a Kerr black hole
    Leloudas, G., Frazer, M., Stone, N. C. et al. (coauthor de Ugarte Postigo, A), 2016, NatAs 1, id. 0002
  • Highly enriched 7Be in the ejecta of Nova Sagittarii 2015 No. 2 (V5668 Sgr) and the Galactic 7Li origin
    Molaro, P.; Izzo, L.; Mason, E.; Bonifacio, P.; Della Valle, M. 2016, MNRAS 462, L117
  • OCTOCAM: a fast multi-channel imager and spectrograph proposed for the Gemini Observatory
    de Ugarte Postigo, A.; Roming, P.; Thöne, C. C.; van der Horst, A. J.; Pope, S.; García Vargas, M. L.; Sánchez-Blanco, E.; Maldonado Medina, M.; Content, R.; Snik, F.; Killough, R.; Winters, G.; Persson, K.; Jeffers, S.; Riva, A.; Bianco, A.; Zanutta, A., 2016, Proceedings of the SPIE, Volume 9908, id. 990840
  • A self-consistent analytical magnetar model: the luminosity of γ-ray burst supernovae is powered by radioactivity
    Cano, Z., Johansson A. K. G., Maeda, K., 2016, MNRAS, 457, 2761
  • A young stellar environment for the superluminous supernova PTF12dam
    Thöne, C.C., de Ugarte Postigo, A., García-Benito, R., et al. 2015, MNRAS, 451, L6
  • The host of the SN-less GRB 060505 in high resolution
    Thöne, C. C.; Christensen, L.; Prochaska, J. X.; Bloom, J. S.; Gorosabel, J.; Fynbo, J. P. U.; Jakobsson, P.; Fruchter, A. S., 2014, MNRAS, 441, 2034
  • Spectroscopy of the short-hard GRB 130603B. The host galaxy and environment of a compact object merger
    de Ugarte Postigo, A., Thöne, C.~C., Rowlinson, A., et al. 2014, A&A,, 563, A62
  • The unusual γ-ray burst GRB 101225A from a helium star/neutron star merger at redshift 0.33
    Thöne, C. C.; de Ugarte Postigo, A.; Fryer, C. L. et al. 2011, Nature, 480, 72

Jobs at HETH

We are currently offering ONE PhD project within the INPhINit call of the CAIXA foundation, Deadline Feb. 6, 2019 (incoming), Feb. 27 (retaining).

    La CAIXA foundation funds 35 PhD positions for "incoming" students (people who have resided <12 months within the last 3 years in Spain/Portugal) and 30 for "retaining" students (the opposite requirement). Candidates are selected in a two stage process: A preselection by an external committee and subsequent matching of the successful candidates with one of the projects offered.
    Duration: 3 years
    - ~1450€ (net) per month in 14 payments
    - A bonus of 7500 EUR if the thesis is handed in within 6 months after finishing the fellowship
    - 3564 EUR/yr for research expenses
    - Standard Spanish employment contract (public health insurance, contributions to pension and unemployment)
    - Extra benefits by the foundation: Mentoring program, yearly 3-5 day training session on carreer development and technology transfer, secondments to other institutions Requirements:
    - Not having yet obtained a PhD and being in the first 4 years of (full-time researcher equivalent) research carreers
    - Fulfill the mobility criteria
    - A completed university degree requiring 300 ECTS credits, of which at least 60 ECTS credits at the master level, or an equivalent degree from a non-European university.
    - B2 or equivalent in English (the call is rather restrictive about it, please read the equivalent recognizable documents in the pdf of the requirements, the deadline to hand in those is Feb. 20!).
    Program overview
    Incoming fellowships
    Call pdf document
    HETH project offered (Area of Knowledge and Disciplines: Physics, Country: Spain, Research Center: IAA-CSIC).

Other funding possibilities (currently no open call):

  • FPU fellowships (PhD students)
    Application deadline around late March. Applicants are required to be enrolled in a master program at very specific dates. Evaluations are in two stages, the first downselection is based purely on university grades after which there is another downselection on project and advisor merits.
    Funding is provided for 4 years on a standard employment contract including all benefits. Salaries are currently about 1000 EUR/month in 14 payments. The applicant can apply for extra funding for visits of 3-5 months at institutes outside Spain each year of the PhD.
  • Marie Curie individual fellowships (postdoc)
    MC-IFs are highly competitive and granted based an innovative research proposal and that should be made in strong collaboration with the hosting group. There are two modalities: incoming fellowships (2 years at a European institute) and outgoing fellowships (2 years outside Europe + 1 year at a European host). Since applications are also based on the achievements and training capabilities of the hosting group, we strongly urge interested applications to contact us early on in order to set up a competitive proposal.
    Deadline: (next deadline: Sept. 2019)
    Duration: 2 years
    Requrements: PhD defended or at least 4 years of full-time research equivalent (e.g. during a PhD).
    Mobility requirement: the applicant cannot have resided in the applying country for more than 12 months in the last 36 months prior to the deadline.
    Salaries: Net salary around 3800 EUR/month (12 payments), research funds of 800 EUR/month.
    Benefits: Standard Spanish employment contracts including public health insurance, pension and unemployment contributions. Some extra benefits from the MC program for familiy members. Familiy members registered in Spain furthermore also qualify for public health insurance.
    Link to the 2018 call (next call published in early summer 2019).
  • CAIXA fellowships (postdoc)
    Private foundation of the CAIXA bank for incoming researchers and researchers already in Spain with very short funding left. Fellowships are highly competitive (22 positions in all of Spain and all areas) and have to be hosted at a ``Severo Ochoa'' excellence center. IAA obtained the excellence certificate in July and hence qualifies as host for these fellowships). Deadline: (maybe new call in Sept. 2019)
    Duration: 3 years
    Requrements: PhD obtained 2 - 7 years before the deadline.
    Mobility requirement: the applicant cannot have resided in the applying country for more than 12 months in the last 36 months prior to the deadline.
    Salaries: Net salary around 3000 EUR/month (14 payments), 5400 EUR for relocation and research funds of 38,000 EUR/y. Additional funding for family members are available.
    Benefits: Standard Spanish employment contracts including public health insurance, pension and unemployment contributions. Some extra benefits from the MC program for familiy members. Familiy members registered in Spain furthermore also qualify for public health insurance.
    Link to the 2018 call.
  • Juan de la Cierva fellowships (postdoc)
    Two modalities: early postdocs ("formación", 1-3 years after the PhD, PhD defended typically a few months before the deadline) and advanced postdocs ("incorporación" 3-5 years after PhD). Both fellowships are for 2 years and postdocs being granted the starting fellowship can apply for the advance one so that they follow one after the other. Current evaluations are based purly on the CV of the applicant and the merits of the group.
    Please contact the PIs if you want to apply as they have to be done jointly by the applicant and the group.
    Deadline: (next deadline: Jan./Feb. 2019)
    Duration: 2 years
    Requirements: PhD defended between 1 and 5 years prior to the deadline (exact dates are published in each call) Salaries: 1450 EUR/month in 14 payments, reserach funds of 3000 EUR/y.
    Benefits: Standard Spanish employment contracts including public health insurance, pension and unemployment contributions.
  • Ramon y Cajal fellowships (postdoc)
    Call published in late fall with deadline in Jan/Feb. For advanced postdocs that aim for a permanent position in Spain. RyC fellows are entitled to ask for additional funding through national Spanish and regional grants. RyC fellowships are applicant based, but due to necessary co-funding through the hosting institute, please contact us before applying if you consider coming to HETH/IAA. Deadline: (next deadline: Jan./Feb. 2019)
    Duration: 5 years
    Requirements: PhD defended up to 9 years prior to the deadline (exact dates are published in each call), delays for childcare times apply. Salaries: 1800 EUR/month in 14 payments, reserach funds of 10k EUR/y for the first 4 years. Benefits: Standard Spanish employment contracts including public health insurance, pension and unemployment contributions.
  • External funding
    We also welcome scientists that come with their own funding from abroad. Whether it is a fully funded PhD or postdoc or you want to stay for a few months working in one of our science areas, please contact the PIs of the group.

HETH is supported by the following funding:

  • Spanish National Research Grant of Excellence under project AYA2017-89384-P "High Energy Transients and their Host: The common, the peculiar and the detailed"
  • Ramón y Cajál fellowships and research funding under contracts RyC-2012-09984 and RyC-2012-09975
  • Juan de la Cierva Incorporación fellowships and research funding IJCI-2015-26153