News & Press releases

Number of entries: 105

03
October 2019

Twin baby stars grow in complex network of gas and dust


Twin baby stars grow in complex network of gas and dust
Pretzel-type filaments
Credit: Felipe O. Alves (MPE)
  • For the first time, high-resolution images obtained with the Atacama Large Millimetre/submillimetre Array (ALMA) show a young stellar binary system in which a complex network of accretion filaments is nurturing two proto-stars. 
  • Each star has a circumstellar disk of its own and together, the stars and their disks, have another, larger, circumbinary disk. 
  • The team was led by Felipe Alves, currently at the Max Planck Institute for Extraterrestrial Physics, who did his doctoral studies at the Institute of Space Sciences (CSIC), under the coordination of IEEC member Dr. Josep Miquel Girart, who is also the third author of the study.
  • The results appear in the journal Science.
Most stars in the Universe come in the form of pairs – binaries – or even multiple star systems. Now, the formation of such a binary star system has been observed for the first time with high-resolution ALMA (Atacama Large Millimetre/submillimetre Array) images.

An international team of astronomers targeted the system [BHB2007] 11, the youngest member of a small cluster of young stellar objects in the Barnard 59 dark nebula, which is part of the cloud of dust and gas called the Pipe nebula. While previous observations showed a rotating and infalling envelope surrounding a circumbinary disk, the new observations now also reveal its inner structure.

“We see two compact sources, that we interpret as circumstellar disks around the two young stars,” explains Felipe Alves from the Max Planck Institute for Extraterrestrial Physics (MPE). The stars grow bigger by pulling matter from these disks. “The size of each of these disks is similar to the asteroid belt in our Solar System and their separation is slightly smaller than our Solar System as a whole.” In addition, both protostars and their circumstellar disks are surrounded by a bigger disk, called a circumbinary disk, with a total mass of about 80 Jupiter masses, which shows a complex network of dust structures distributed in spiral shapes, resembling a pretzel.

Astronomers have observed an accretion process in two stages. In the first stage, mass is transferred from the big, circumbinary disk to the circumstellar disks. In the second stage, mass is transferred from the circumstellar disks to the stars. 
“Thanks to the power of ALMA, we have managed to peer deeper into the complex system of young binary stars and gain a better understanding of how such systems form, as well as find out that the formation of rocky planets in such environments may be possible. Using this knowledge, we can now study more similar systems to further describe the conditions that allow for multiple star systems to form,” declared Dr. Josep Miquel Girart, a researcher from the Institute of Space Studies of Catalonia (IEEC) at the Institute of Space Sciences (ICE, CSIC) and third author of the study.

Observatories and Instruments
The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

Links
More information
This research is presented in a paper entitled “Gas flow and accretion via spiral streamers and circumstellar disks in a young binary protostar”, by F. O. Alves, P. Caselli, J. M. Girart  et al., to appear in the journal Science on 4 October 2019.

The Institute of Space Studies of Catalonia (IEEC  — Institut d’Estudis Espacials de Catalunya) promotes and coordinates space research and technology development in Catalonia for the benefit of society. IEEC fosters collaborations both locally and worldwide and is an efficient agent of knowledge, innovation and technology transfer. As a result of over 20 years of high-quality research, done in collaboration with major international organisations, IEEC ranks among the best international research centers, focusing on areas such as: astrophysics, cosmology, planetary science, and Earth Observation. IEEC’s engineering division develops instrumentation for ground- and space-based projects, and has extensive experience in working with private or public organisations from the aerospace and other innovation sectors. 

IEEC is a private non-profit foundation, governed by a Board of Trustees composed of Generalitat de Catalunya and four other institutions that each have a research unit, which together constitute the core of IEEC R&D activity: the University of Barcelona (UB) with the research unit ICCUB — Institute of Cosmos Sciences; the Autonomous University of Barcelona (UAB) with the research unit CERES — Center of Space Studies and Research; the Polytechnic University of Catalonia (UPC) with the research unit CTE — Research Group in Space Sciences and Technologies; the Spanish Research Council (CSIC) with the research unit ICE — Institute of Space Sciences. IEEC is integrated in the CERCA network (Centres de Recerca de Catalunya).

Contacts

IEEC Communication Office
Barcelona, Spain
Rosa Rodríguez Gasén
Email: comunicacio@ieec.cat 

Lead Scientist
Garching bei München, Germany
Felipe Alves
Center for Astrochemical Studies
Max Planck Institute for Extraterrestrial Physics
Tel: +49 89 30000 3897
Email: falves@mpe.mpg.de

Third author
Cerdanyola del Vallès, Catalonia, Spain
Josep Miquel Girart
Institute of Space Sciences (ICE, CSIC) / IEEC
Email: girart@ice.cat

Press Release elaborated by the IEEC Comunication Department
26
September 2019

CARMENES: Giant exoplanet around a small star challenges our understanding of how planets form


CARMENES: Giant exoplanet around a small star challenges our understanding of how planets form
Infographic of GJ3512 orbit comparison
Credit: Guillem Anglada-Escude - IEEC, using SpaceEngine.org. Distribution license: Creative Commons Attribution 4.0 International (CC BY 4.0).
  • A study from the CARMENES consortium led by IEEC researchers at ICE (CSIC) reports the discovery of an anomalous planetary system around the nearby red dwarf GJ 3512, located at approximately 30 light-years from us. Although the star is only about a tenth of the mass of the Sun, it possesses at least one gas giant planet.
  • This planet probably formed from an unstable disc around the young star which broke up into clumps. This contrasts with how the majority of massive planets are believed to form, where a planet grows slowly as gas falls onto a solid core.
  • The signal of the planet is clearly detected with both the visible and infrared arms of the CARMENES spectrograph at the Calar Alto Observatory . This makes it the first exoplanet unambiguously discovered by a new-generation infrared high-resolution spectrometer.
  • For this discovery, the CARMENES consortium used, among others, IEEC’s 80-cm diameter Joan Oró Telescope (TJO) at the Montsec Observatory and the facilities at Observatorio de Sierra Nevada (IAA, CSIC).
  • The result will be published in the forthcoming issue of the journal Science.
Astronomers from the CARMENES consortium, led by Juan Carlos Morales, a researcher from the Institute of Space Studies of Catalonia (IEEC) at the Institute of Space Sciences (ICE, CSIC) have discovered one, possibly even two, gas giant planets orbiting the nearby red dwarf star GJ 3512.

To discover the planets, the astronomers used the Doppler technique, which monitors the back-and-forth motion of a star when it is orbited by one or more planets. The star however almost did not make it into the list of observational targets.

“CARMENES was built to find planets around the smallest stars, but we also wanted them as bright as possible. Initially, this star was not included in our observation list because it was too faint,” declares Ignasi Ribas, CARMENES project scientist and Director of IEEC. “We then realised we didn’t have enough small stars in the sample and we added a few, at the very last minute. We were lucky to do so because otherwise we would have never made this discovery”.

The 140 observations clearly reveal a motion of the star caused by a massive companion in both the optical and infrared arms of the CARMENES spectrograph. The infrared arm of CARMENES was the core contribution of the Spanish institutes to the consortium and it was built at CSIC's Instituto de Astrofísica de Andalucía. The instrument is in operation since 2016 at the 3.5 meters telescope in the Calar Alto Observatory in Almeria (Spain).

“As their name indicates, red dwarfs emit most of their light in the red and near infrared parts of the spectrum. CARMENES was designed to make optimal use of all the light wavelengths where the stars are brighter,” explains Ansgar Reiners, from the Institute for Astrophysics Göttingen, in Germany. “Despite the fact that optical high-resolution and stabilised spectrographs have existed for a while, for example HARPS, near-infrared ones represent a new technology.”

With this discovery, CARMENES achieves the first detection of an exoplanet solely using a new-generation near-infrared precision instrument, highlighting again the leading role played by European researchers in the field of exoplanets. An earlier detection of an exoplanet using an infrared spectrometer required the use of several other facilities to confirm it [2].

After a few initial observations, this target caught the attention of scientists and triggered further monitoring. “The star was showing a rather strange behaviour very early on. Its velocity was changing very rapidly, and consistently in both wavelength channels of the instrument, indicating the presence of a massive companion, an anomalous feature for a red dwarf,” explains Juan Carlos Morales.

GJ 3512 is almost identical to Proxima Centauri and only a bit more massive than Teegarden’s star and TRAPPIST-1 , which all host terrestrial planets in temperate orbits, but no gas giants. “It is becoming the norm to expect small planets around these small stars, so we initially thought this large motion had to be caused by another star in a very long orbital period. We kept observing it, but on low priority. To our surprise, the motion started to repeat again in the next season, indicating that it was actually produced by a planet. At that point, GJ 3512 finally made it to the top priority list,” explains Dr. Morales.

“IEEC’s 80-cm diameter Joan Oro Telescope at the Montsec Observatory played a significant role in the discovery, allowing the astronomers to derive the rotational period of the system at 87 days, an important step to confirm that the signal is a planet and not stellar activity, as well as to estimate the age of the system”, declared Enrique Herrero, IEEC researcher.

Planet formation models should be able to explain how planetary systems come into existence around stars like our Sun, but also around smaller stars. Until now, the so-called “core accretion model” for planet formation was considered sufficient to explain Jupiter and Saturn in our Solar System, and many other gas giant planets discovered around other stars.

The “core-accretion” model assumes that planets form in two phases: at first, rocky cores, the size of a few Earth masses, form a nucleus within the protoplanetary disk and then, when a critical mass is reached, they start to accumulate and retain large amounts of gas until they reach the mass of Jupiter or more.

Low-mass stars should have proportionately low-mass disks, so the amount of available material in the disk to form planets is also significantly reduced. The presence of a gas giant around a low-mass star indicates that either the original disk was anomalously massive [3] or that the core-accretion scenario does not apply in this case. Moreover, this planet is on an eccentric orbit, which is the smoking gun of a past event indicating the presence of another massive planet that was ejected from the system in a chaotic interaction with the current planet, adding a wandering planet in the galactic void.

Researchers from IEEC, the Max Planck Institute for Astronomy (MPIA) and other CARMENES institutes established a collaboration with the planet formation groups at Lund Observatory in Sweden and Bern University in Switzerland , all of them world leaders in planet formation theory, to study plausible formation scenarios for this system.

“After running multiple simulations and long discussions among the different groups to try to explain the system, we concluded that our most up-to-date models could never allow the formation of even one massive planet, let alone two,'' explains Alexander Mustill, a Senior Research Fellow at Lund Observatory.

But there is a possible alternative planet formation scenario that could save the day. The “disk-instability model” advocates that some or maybe all gas giant planets can directly form from the gravitational self-accumulation of gas and dust instead of requiring a “seed” core. Although this scenario is plausible, it has been mostly ignored so far because it fails to explain other trends observed for the population of gas giant planets. This new CARMENES discovery is bound to change this.

“I find it fascinating how a single anomalous observation has the potential to produce a paradigm shift in our thinking, in something as essential as the formation of planets and, therefore, in the big picture of how our own Solar System came into existence,'' declares Juan Carlos Morales.

The CARMENES consortium keeps monitoring the star in order to confirm the existence of a second, possibly a Neptune-like object, in a longer orbital period. Besides, the scientists have not discarded the presence of temperate terrestrial planets orbiting GJ 3512. More data will tell if it turns out to be a small scale Solar System.

Notes
[1] Technically speaking, the first solid exoplanet detection reported using a high resolution infrared spectrometer was done with CSHELL at IRTF, and corresponds to a massive object at the limit between a planet and a brown dwarf (~13 Mjup) in orbit around CI Tau . CARMENES is a new-generation instrument specifically built for exoplanet searches. Since CARMENES started operations, a number of similar instruments came on-line at top world observatories, such as the Subaru Telescope and the Canada-France-Hawaii Telescope, both in Mauna Kea, Hawaii.
[2] The existence of such anomalously massive disks is currently not confirmed by observations of star forming regions.

Observatories and Instruments
The CARMENES ( Calar Alto high-Resolution search for M dwarfs with Exoearths with Near-infrared and optical Échelle Spectrographs) instrument is a high-resolution optical and near infrared spectrograph built in collaboration by various Spanish and German research institutions, and it is operated by the Calar Alto observatory (Spain) .

Links
- CARMENES
- Calar Alto Observatory
- IEEC
- Montsec Observatory

More information
This research is presented in a paper entitled "A giant exoplanet orbiting a very-low-mass star challenges planet formation models", by J. C. Morales et al., to appear in the journal Science on 27 September 2019.

The Institute of Space Studies of Catalonia (IEEC — Institut d’Estudis Espacials de Catalunya) promotes and coordinates space research and technology development in Catalonia for the benefit of society. IEEC fosters collaborations both locally and worldwide and is an efficient agent of knowledge, innovation and technology transfer. As a result of over 20 years of high-quality research, done in collaboration with major international organisations, IEEC ranks among the best international research centers, focusing on areas such as: astrophysics, cosmology, planetary science, and Earth Observation. IEEC’s engineering division develops instrumentation for ground- and space-based projects, and has extensive experience in working with private or public organisations from the aerospace and other innovation sectors.

IEEC is a private non-profit foundation, governed by a Board of Trustees composed of Generalitat de Catalunya and four other institutions that each have a research unit, which together constitute the core of IEEC R&D activity: the University of Barcelona (UB) with the research unit ICCUB — Institute of Cosmos Sciences; the Autonomous University of Barcelona (UAB) with the research unit CERES — Center of Space Studies and Research; the Polytechnic University of Catalonia (UPC) with the research unit CTE — Research Group in Space Sciences and Technologies; the Spanish Research Council (CSIC) with the research unit ICE — Institute of Space Sciences. IEEC is integrated in the CERCA network (Centres de Recerca de Catalunya).

Contacts
IEEC Public Communication Office Barcelona, Spain
Rosa Rodríguez Gasén
E-mail: comunicacio@ieec.cat

Institute of Space Sciences (ICE, CSIC) Barcelona, Spain
Juan Carlos Morales
IEEC member, researcher
E-mail: morales@ice.cat

Press Release elaborated by the IEEC Communication Office in collaboration with Science Wave.
24
September 2019

PAZ Radio Occultation profiles being operationally assimilated into a numerical weather prediction model


PAZ Radio Occultation atmospheric profiles being operationally assimilated into the USA Navy numerical weather prediction model
Reduction of the weather forecast error due to PAZ radio occultation observations.
NRL and FNMOC
Helsinør, Denmark, September 24, 2019,

Researchers of the U.S. Naval Research Laboratory (NRL) announced that data acquired by the Radio Occultation and Heavy Precipitation experiment aboard PAZ (ROHP-PAZ) are being assimilated operationally into the US Navy Global Environmental Model (NAVGEM) which is run operationally by Fleet Numerical Meteorology and Oceanography Center (FNMOC) since 15t August 2019. Real time monitoring of the innovations are available to the public at: https://www.nrlmry.navy.mil/metoc/ar_monitor/. The announcement was made at the 7th International Radio Occultation Working Group (IROWG-7) meeting and EUMETSAT ROM-SAF User Workshop held in Helsingør, Denmark. NRL provided the capability to assimilate PAZ ROHP-PAZ to FNMOC, and continues to contribute to the development and maintenance of the NAVGEM system for weather forecasts and related services. The present quality levels of the PAZ data have shown consistent positive impact to weather analysis and forecasts similar to the other radio occultation missions. This effort is extremely useful to the RO community, and a significant step towards the assimilation of PAZ data into other operational weather prediction models.

The ROHP-PAZ experiment is led by the Earth Observation group at the Institute of Space Sciences (ICE-CSIC) and Institute of Space Studies of Catalonia (IEEC). Signals transmitted by the Global Positioning System (GPS) are acquired at the PAZ satellite when these transmitters are setting behind the limb of the Earth (‘occulting’). These signals contain information about the vertical structure of thermodynamic variables of the atmosphere, improving the weather forecast when injected into the prediction models. PAZ radio occultation data are downloaded to the ground and processed to intermediate products in near-real time by the USA National Oceanic and Atmospheric Administration (NOAA) and the University Corporation of Atmospheric Research (UCAR), through agreements with the ICE-CSIC/IEEC. These products, suitable for assimilation into the numerical weather prediction models, are currently being disseminated in near real time to NOAA related centers, while waiting for prompt dissemination to weather services worldwide through the Global Telecommunication System of the World Meteorological Organization (WMO).

ROHP-PAZ is an opportunistic experiment aboard PAZ low Earth orbiter, a satellite owned, operated and exploited by HISDESAT. The experiment is funded by the Spanish Ministry of Science, Innovation and Universities.

 
23
September 2019

Investigadores del CSIC participan en la mayor expedición científica al Ártico


Investigadores del CSIC participan en la mayor expedición científica al Ártico
El rompehielos alemán Polarstern, que transporta a la expedición MOSAIC
Instituto Alfred Wegener
  • La misión MOSAIC, a bordo del rompehielos Polarstern, quedará varada en la banquisa de hielo durante un año para medir los cambios ambientales debidos al cambio climático
  • Investigadores del CSIC estudiarán la interacción de la vida marina en la formación de nubes y el uso de tecnología satélite para medir el estado y el grosor del hielo
  • La expedición está formada por un consorcio internacional con el CSIC como socio español financiado por la Agencia Estatal de Investigación
Tres equipos de investigadores del Consejo Superior de Investigaciones Científicas (CSIC) participa en la mayor expedición científica al Ártico de la historia. Se trata del proyecto MOSAIC, que, a bordo del rompehielos de investigación alemán Polarstern, partió de Tromso (Noruega) el viernes para pasar un año atrapado en el hielo a la deriva a través del Océano Ártico. El objetivo de la misión es estudiar el Ártico como epicentro del calentamiento global para obtener datos que permitan comprender mejor el cambio climático global. El proyecto reúne 600 investigadores de 19 países que trabajarán de forma rotativa, e incluye tres equipos de investigación españoles, todos del CSIC, procedentes del Instituto de Ciencias del Mar y del Instituto de Ciencias del Espacio/Instituto de Estudios Espaciales de Cataluña, y financiados por la Agencia Estatal de Investigación.

El plan de la expedición MOSAIC prevé que el rompehielos Polarstern, del Instituto Alfred Wegener (Alemania), navegue en dirección noreste hacia el mar de Laptev, en la Siberia central, y se adentre en la banquisa de hielo, en un emplazamiento seleccionado a partir de datos de satélite y radar, para quedar allí deliberadamente atrapado en el hielo. Una vez fijado, el rompehielos viajará con el hielo a lo largo de una ruta conocida como deriva transpolar hacia el polo norte, lo cruzará y luego se dirigirá hacia el sur para desembocar en el estrecho de Fram, entre Groenlandia y el archipiélago de las Svalbard (Noruega), entre 12 y 14 meses después.

De este modo, el Polarstern se convertirá en un centro de investigación itinerante, el llamado MOSAIC, o Multidisciplinary drifting Observatory for the Study of Arctic Climate (Observatorio multidisciplinar a la deriva para estudiar el clima ártico). La expedición contará con un equipo de 60 investigadores expertos en investigación ártica, más unos 40 tripulantes (en turnos de unos dos meses), que operarán su instrumental a bordo y en el hielo. Allí los científicos estudiarán la atmósfera, el mar y el hielo, y cómo interactúan entre ellos, con el objetivo de comprender mejor cómo afectará el calentamiento global a la región ártica.

Desde el Instituto de Ciencias del Mar, el investigador del CSIC Manuel Dall’Osto viajará a bordo del Polarstern entre julio y septiembre de 2020 para realizar mediciones atmosféricas y estudiar el impacto de la vida marina en la formación de las nubes. “Las nubes son clave para regular la temperatura del planeta. Sin nubes tendríamos una Tierra mucho más cálida. Pero no entendemos suficientemente bien cómo se forman y se destruyen, y eso nos está limitando mucho en las proyecciones de clima y de cambio climático”, añade.  “Con nuestra campaña queremos saber qué sinergia se establece entre la materia de origen biológico y las nubes, qué tipo de plancton favorece más la formación de nubes y en qué regiones del océano esta relación es más importante”, explica Dall’Osto.

También desde el Instituto de Ciencias del Mar, otro equipo de investigadores estudiará la masa y el grosor del hielo marino mediante mediciones vía satélite. Los científicos desplegarán un novedoso radiómetro de microondas, montado sobre un trineo, que permitirá medir el espesor del hielo durante todo el año. El radiómetro opera en la frecuencia 1.4GHz y ha sido diseñado y construido por la empresa española Balamis. “El Ártico es una de las regiones más remotas del planeta, y de más difícil acceso, por lo que para monitorizar de forma continua el estado del hielo es imprescindible recurrir a la información vía satélite”, explica la investigadora del CSIC Carolina Gabarro, directora del estudio. “Nuestro radiómetro permitirá mejorar los modelos de transferencia radiativa del hielo marino y la nieve para lograr estimaciones más fiables del espesor del hielo desde los satélites”, añade.

“La información proporcionada por estos satélites sobre el hielo marino son cruciales para comprender los cambios que afronta el Ártico bajo la amenaza del cambio climático y, en particular, para estudiar la evolución de la masa de hielo marino y el equilibrio ártico”, detalla Gabarro. “Todas estas medidas permitirán mejorar los modelos matemáticos, y por lo tanto la información geofísica que nos ofrecen los satélites SMOS (de la Agencia Espacial Europea) y SMAP (de la NASA) que miden el grosor del hielo marino”, detalla la investigadora.

El tercer equipo español que trabaja en la expedición MOSAIC pertenece al Instituto de Ciencias del Espacio (ICE, CSIC) y al Instituto de Estudios Espaciales de Cataluña (IEEC) y estudiará la interacción entre el hielo marino y las señales de navegación transmitidas desde satélite (como los GPS). “Estas señales, después de reflejarse en el hielo, pueden ser detectadas y analizadas para extraer información del hielo marino: su grosor, rugosidad, cantidad de sal, presencia de agua en superficie, etc”, explica la investigadora del CSIC Estel Cardellach, del ICE/IEEC.

El estudio del ICE/IEEC se realizará mediante dos experimentos: uno instalado en la banquisa de hielo y otro a bordo de un avión de investigación que sobrevolará la zona y recogerá grandes cantidades de datos, que se sumarán a los datos obtenidos por otros grupos de investigación de MOSAIC. “Si los estudios confirman que esta técnica de medición mediante señales de navegación proporciona una gran precisión, se podría aplicar desde satélites de bajo coste para monitorizar los polos de forma continua”, señala Cardellach.

El Ártico, centinela del cambio climático
Las temperaturas ascienden en todo el planeta, debido principalmente a la actividad humana que emite gases de efecto invernadero a la atmósfera, pero en el Ártico las temperaturas ascienden el doble de rápido que en otras regiones, y sus efectos son más evidentes que en ningún otro lugar. Por ejemplo, el hielo se reduce y se hace más delgado a medida que el Ártico se calienta.

El Ártico es una de las zonas más remotas del planeta, sólo accesible durante unos pocos meses en verano, cuando el hielo se derrite. Como la expedición MOSAIC viajará a la deriva durante un año, permitirá obtener datos a lo largo de todo el ciclo anual del hielo, desde su crecimiento hasta que se derrita.

Nota de prensa redactada por el Departamento de Comunicación del CSIC
16
September 2019

Mysteriously in-sync pulsar challenges existing theories


Mysteriously in-sync pulsar challenges existing theories
Transitional millisecond pulsar PSR J1023+0038
ESA
Researchers from the Institute of Space Studies of Catalonia (IEEC) at the Institute of Space Sciences (ICE, CSIC) have contributed to a research study that, for the first time, detected synchronised pulses of optical and X-ray radiation from a mysterious pulsar. The observations indicate that a new physical mechanism might be needed to explain the behaviour of fast-spinning sources like this one, known as transitional millisecond pulsars.

The discovery was made as part of a two-day observation campaign spearheaded in 2017 by ESA’s XMM-Newton X-ray observatory and other telescopes. The group of IEEC researchers at ICE, CSIC — Francesco Coti Zelati, Nanda Rea, Santiago Serrano, and Diego Torres — have taken part in both the X-ray and optical observations, using, among others, the Montsec Observatory (Observatori Astronòmic del Montsec, OAdM) managed by IEEC. The combination of various space- and ground-based facilities [1] allowed the international team of astronomers to measure with very high temporal resolution the two types of radiation coming from the ultrafast rotating pulsar. 

The pulsar [2] analysed in this study, known as PSR J1023+0038, spins around its axis within a few thousandths of a second. Such pulsars are classed as millisecond pulsars, some of which are also sucking in matter from a companion star – as is the case of this pulsar. 

Earlier studies had shown that this pulsar belongs to the rare category of so-called ‘transitional millisecond pulsars’ that periodically switch between two different modes of emissions – in X-rays and radio waves. 

According to the leading model explaining this behaviour, the accretion of matter from the companion star gives rise to the pulsed X-ray emissions, while the radio signal is thought to result from the rotation of the pulsar’s magnetic field. 

Further observations of PSR J1023+0038, however, revealed that an entirely different explanation might be needed to understand this class of sources. 

“PSR J1023+0038 is the very first milisecond pulsar discovered with pulsations also in the optical band,” said Alessandro Papitto from INAF in Rome, Italy, lead author of the new study. 

The latest data show that the optical pulses in PSR J1023+0038 appear and disappear at exactly the same time as the X-ray ones. 

Conventional models could not explain the synchronised pulses so the team had to identify a new scenario that could explain the data. IEEC researcher Diego Torres was part of the group that put forward this new model to explain the detection, while also highlighting the existence of a small lag between the two emissions, yet to be further confirmed observationally.

“​Until now, we thought that the pulsed X-ray emissions originated in a different process than the optical radiation. We also expected these processes to take place one after the other, but this is not the case for PSR J1023+0038. The synchronised pulses are an indication that they have the same origin​,” says Diego Torres. 

The new model states that the pulsar might be emitting a strong electromagnetic wind, which then interacts with the accretion disc around the system. As the pulsar wind hits matter in the accretion disc, it creates a massive shock, which accelerates electrons in the wind to extremely high speeds. The electrons then interact with the wind’s magnetic field, producing powerful beams of synchrotron radiation that can be observed in the optical and X-ray bands at the same time. All of this would happen at a very close distance from the pulsar, giving rise to the concept of mini pulsar wind nebula.

“​The transitional pulsar J1023 + 0038 is one of the most interesting sources we know. Its multi-frequency variability is incredibly rich, and allows us to study the relationship between the magnetic field and matter in extreme conditions​," concludes Torres as he is looking forward to further observations with future technologies. 

For more information on this study, please visit ESA​'s press release and/or ​access the scientific paper “​Pulsating in unison at optical and X-ray energies: Simultaneous high-time resolution observations of the transitional millisecond pulsar PSR J1023+0038”​ by A. Papitto, F. Ambrosino, L. Stella, D. F. Torres, F. Coti Zelati et al.; published in The Astrophysical Journal. 

Notes
[1] The study combines X-ray observations from ESA’s XMM-Newton and NASA’s NuSTAR and NICER X-ray observatories with ultraviolet observations from NASA’s Swift, optical observations from INAF’s optical Galileo National Telescope (TNG), equipped with the fast photometer SiFAP, and the Nordic Optical Telescope (NOT), both located at Roque de los Muchachos Observatory, in La Palma, Canary Islands, Spain, as well as from the Telescopi Joan Oró (TJO), located at the Montsec Observatory in the Catalan pre-Pyrenees, Spain, and infrared observations from the Gran Telescopio Canarias (GTC), also on the island of La Palma.

[2] Pulsars are highly magnetised, fast spinning neutron stars – the relics of massive stars. They are very dense objects, comprising up to two times the mass of the Sun within a radius of only ten km. 

This Press Release has been elaborated by IEEC Comunication Department

Contacts
IEEC Communication Office 

Barcelona, Spain
Rosa Rodríguez Gasén
E-mail: ​comunicacio@ieec.cat 

Lead Scientist at ICE Barcelona, Spain
Diego Torres
Institute of Space Science
E-mail: ​dtorres@ice.csic.es 
17
July 2019

Regular release of RHOP-PAZ dual-polarization data starts today


Regular and continuous release of the RHOP-PAZ experiment data has started on July 17, 2019. The access point is at UCAR CDAAC servers.
Snapshot of PAZ access point at UCAR's CDAAC server
The first dual-polarized GNSS radio occultation data, acquired by ICE-CSIC/IEEC experiment aboard PAZ (RHOP-PAZ), have been released by UCAR. The initial batch of files covers the period from May 10, 2018 to April 29, 2019, and it will be regularly updated from this moment on. The post-processing products will be continuously provided with several weeks latency. The data access point is at:

https://cdaac-www.cosmic.ucar.edu/cdaac/products.html
05
July 2019

EXTP Wide Field Monitor (WFM) meeting + EXTP Science Requirements meeting (9-12 July 2019)


International meeting of the WFM instrument team in the Institut de Ciències de l'Espai (ICE, CSIC)
Artist impression of the eXTP satellite
https://www.isdc.unige.ch/extp/
International meeting of the WFM instrument team will be celebrated in the Institut de Ciències de l'Espai (ICE, CSIC) in Barcelona (Spain), in order to prepare the documentation package to be submitted to ESA at the end of July 2019, and to discuss the tasks related to phase B1.

The WFM team meeting will be followed by the international meeting for the finalization of the eXTP Science Requirements documents.

More information about the project in https://www.isdc.unige.ch/extp/
18
June 2019

CARMENES finds two temperate Earth-mass planets around a nearby small star


CARMENES finds two temperate Earth-mass planets around a nearby small star
Planets in the habitable zone around a star
Image: Chester Harman / Planets: PHL @ UPR Arecibo, NASA/JPL
Researchers from the Institute of Space Sciences (ICE, CSIC) and from Institute of Space Studies of Catalonia (IEEC) have participated in an international study carried out by the CARMENES consortium, which has discovered two small, terrestrial planets around Teegarden’s Star. The planets have masses similar to Earth and their temperatures could be mild enough to sustain liquid water on their surfaces. Observations were carried out with the CARMENES instrument in Calar Alto (Spain), as well as several other smaller complementary facilities, including IEEC’s Telescopi Joan Oró, at the Montsec Astronomical Observatory. The scientific paper is led by researchers at the University of Göttingen and appears in Astronomy & Astrophysics.

At a distance of only 12.5 light years, Teegarden’s Star is the 24th nearest star system to ours, and one of the smallest red dwarf stars known. Despite its proximity and due to its faintness, Teegarden’s Star was only identified in 2003.

“We have been observing this star with the CARMENES instrument since the beginning of the survey three years ago to measure its motion very precisely” explains Dr. Mathias Zechmeister, a postdoctoral researcher at the University of Göttingen (Germany), and lead author of the publication.

The method used to detect the planets was the so-called Doppler technique. A planet orbiting a star causes a small back-and-forth reflex motion. This motion induces a very subtle Doppler effect on the star light, which is then measured down to a precision of 1 meter per second with CARMENES, the equivalent of walking speed, or 3.6 km/h. Small planets produce a small signal, but their signals are easier to detect on small red dwarfs like Teegarden’s Star rather than on a star like the Sun because the reflex motion is larger and it repeats more often.

“CARMENES is the first high-precision spectrometer in operation specifically designed to find planets using this ‘red dwarf advantage’,” adds Mathias Zechmeister. Teegarden’s temperature is only 2600ºC (compared to the 5500ºC of the Sun), it is 1500 times fainter and ten times less massive than our Sun. As a result, it radiates most of its energy in the red and infrared which made it an ideal target for the CARMENES survey.

The Doppler measurements of Teegarden’s Star showed the presence of at least two signals, now reported as the two new exoplanets, Teegarden’s Star b and c. Obtaining a robust detection with a new instrument required the collection of over 200 measurements. Based on the measured motion, the researchers can deduce that Teegarden’s Star b has a mass similar to that of the Earth, it orbits the star every 4.9 days at about 2,5% the Earth-Sun distance. Teegarden’s Star c is also similar to the Earth in terms of mass, completes its orbit in 11.4 days and is located at 4,5% the Earth-Sun distance. Since Teegarden’s Star radiates much less energy than our Sun, the temperatures on these planets should be mild and they could, in principle, hold liquid water on their surfaces, especially the outer one, Teegarden’s Star c. This kind of planets is the primary target for future searches for life beyond our Solar System.

A major milestone of the CARMENES project
As opposed to previous CARMENES discoveries that combined measurements from several instruments, such as Barnard’s star b, all high-precision Doppler measurements and follow-up observations used for this finding have been obtained by the CARMENES consortium. Several groups within the consortium used smaller telescopes to monitor changes in the brightness of the star to rule out alternative explanations such as star spots or other surface features. The follow-up activities included intensive photometric campaigns at the 1.23-m Calar Alto Telescope/CSIC, the Sierra Nevada Observatory/IAA-CSIC and the Telescopi Joan Oró-Montsec/IEEC, among others.

“This discovery is a great success for the CARMENES project, which was specifically designed to search for planets around the least massive stars“, says Dr. Ignasi Ribas, a researcher from IEEC at ICE/CSIC, and project scientist of CARMENES. The new planets are number ten and eleven in the CARMENES exoplanet discovery tally, and the search continues.

“Both planets may be part of a larger system,'' says Prof. Stefan Dreizler from University of Goettingen and co-author of the study. “Very low-mass stars seem to have densely populated planetary systems“ More data may reveal an even richer system.

“The unique feature of our instrument, which allows it to observe simultaneously in the visible and near infrared, is fundamental to confirm the nature of the signals detected with both channels as due to the presence of planets in orbit, since in this case, the amplitude of the signal does not depend on the channel with which it is measured, contrary to what happens when the signal is due to the star’s intrinsic variability,” points out Dr. Pedro Amado from IAA/CSIC, and deputy principal investigator of CARMENES.

More information
The CARMENES (Calar Alto high-Resolution search for M dwarfs with Exoearths with Near-infrared and optical Échelle Spectrographs) instrument is a high-resolution optical and near-infrared spectrograph built in collaboration by 11 Spanish and German research institutions, and it is operated by the Calar Alto observatory (Spain). CARMENES has been working non-stop since 2016.
 
Contacts
IEEC Public Information Office
Barcelona, Spain
Rosa Rodríguez Gasén
E-mail: comunicacio@ieec.cat
 
Main Scientist at IEEC
Barcelona, Spain
Ignasi Ribas
Institute of Space Science (ICE-CSIC)
Institute of Space Studies of Catalonia (IEEC)
E-mail: iribas@ice.cat

This Press Release is an adaptation of the PR elaborated by IEEC Comunication Department
14
May 2019

Sant Cugat Forum on Astrophysics: Workshop on Polarization in Protoplanetary Disks and Jets


Workshop on Polarization in Protoplanetary Disks and Jets. Sant Cugat del Vallès, May 20-24, 2019
Workshop on Polarization in Protolanetary Disks and Jets
The study of the formation and evolution of protoplanetary disks around young stars saw a tremendous boost by the advent of ALMA and the development of new capabilities in the infrared and radio telescopes, thanks to the huge combined improvement in sensitivity, angular resolution, and image fidelity. However, the role of magnetic fields in the formation and evolution of disks around young stars is still a poorly understood topic. Are protoplanetary disks and protostellar jets magnetized? Polarimetric observations are the primary means to obtain information regarding the magnetic fields. However, this technique can be hampered by other polarization mechanisms such as dust self-scattering, radiation alignment of aspherical grains or anisotropic resonant scattering of linear polarization of molecular lines. The main goal of this focused meeting is to bring together observers and theoreticians interested in the study of magnetic fields in protoplanetary disks and protostellar jets as well as polarization mechanisms to review the current state of the research and explore effective means to probe magnetic fields.
03
May 2019

Modified Gravity and Cosmology Workshop - 8-10 May 2019, Barcelona, Spain


Modified Gravity and Cosmology Workhop
Modified Gravity and Cosmology Workhop 8-10 May 2019, Barcelona, Spain
The Workshop is open to topics related to cosmology and theoretical physics, including:
  • Cosmological models: modified gravities, f(R) theories, and the like, non-local models.
  • Possibility of Observing Modified Gravity in an Astrophysical Level (Neutron Stars)
  • Quantum Gravity
  • Quantum Cosmology and Loop Quantum Cosmology
  • Quantum vacuum and the Casimir Effect
  • The cosmological constant problem.
  • Mathematical physics techniques for quantum vacuum studies

 
Institute of Space Sciences (IEEC-CSIC)

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08193 Barcelona.
Phone: +34 93 737 9788
Email: ice@ice.csic.es
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An institute of the Consejo Superior de Investigaciones Científicas

An institute of the Consejo Superior de Investigaciones Científicas
Affiliated with the Institut d'Estudis Espacials de Catalunya

Affiliated with the Institut d'Estudis Espacials de Catalunya