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Author Allen, N.H.; Espinoza, N.; Jordan, A.; Lopez-Morales, M.; Apai, D.; Rackham, B.V.; Kirk, J.; Osip, D.J.; Weaver, I.C.; McGruder, C.; Ceballos, K.O.; Reggiani, H.; Brahm, R.; Rodler, F.; Lewis, N.K.; Fraine, J.
Title ACCESS: Tentative Detection of H2O in the Ground-based Optical Transmission Spectrum of the Low-density Hot Saturn HATS-5b Type
Year 2022 Publication Astronomical Journal Abbreviated Journal Astron. J.
Volume 164 Issue 4 Pages 153
Keywords BAYESIAN-INFERENCE; EXOPLANET; SKY; ATMOSPHERES; EFFICIENT; TOOL; CHEMISTRY; ASTROPY
Abstract We present a precise ground-based optical transmission spectrum of the hot Saturn HATS-5b (T (eq) = 1025 K), obtained as part of the ACCESS survey with the IMACS multi-object spectrograph mounted on the Magellan Baade Telescope. Our spectra cover the 0.5-0.9 mu m region and are the product of five individual transits observed between 2014 and 2018. We introduce the usage of additional second-order light in our analyses, which allows us to extract an “extra” transit light curve, improving the overall precision of our combined transit spectrum. We find that the favored atmospheric model for this transmission spectrum is a solar-metallicity atmosphere with subsolar C/O, whose features are dominated by H2O and with a depleted abundance of Na and K. If confirmed, this would point to a “clear” atmosphere at the pressure levels probed by transmission spectroscopy for HATS-5b. Our best-fit atmospheric model predicts a rich near-IR spectrum, which makes this exoplanet an excellent target for future follow-up observations with the James Webb Space Telescope, both to confirm this H2O detection and to superbly constrain the atmosphere's parameters.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6256 ISBN Medium
Area Expedition Conference
Notes WOS:000856537200001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1650
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Author Carone, L.; Molliere, P.; Zhou, YF.; Bouwman, J.; Yan, F.; Baeyens, R.; Apai, D.; Espinoza, N.; Rackham, BV.; Jordan, A.; Angerhausen, D.; Decin, L.; Lendl, M.; Venot, O.; Henning, T.
Title Indications for very high metallicity and absence of methane in the eccentric exo-Saturn WASP-117b Type
Year 2021 Publication Astronomy & Astrophysics Abbreviated Journal Astron. Astrophys.
Volume 646 Issue Pages A168
Keywords methods: observational; planets and satellites: atmospheres
Abstract Aims. We investigate the atmospheric composition of the long-period (P-orb = 10 days) eccentric exo-Saturn WASP-117b. WASP-117b could be similar in atmospheric temperature and chemistry to WASP-107b. In mass and radius, WASP-117b is similar to WASP-39b, which allows a comparative study of these planets.Methods. We analyzed a near-infrared transmission spectrum of WASP-117b taken with the Hubble Space Telescope (HST) WFC3 G141, which was reduced with two independent pipelines. High-resolution measurements were taken with VLT/ESPRESSO in the optical.Results. We report the robust (3 sigma) detection of a water spectral feature. In a 1D atmosphere model with isothermal temperature, uniform cloud deck, and equilibrium chemistry, the Bayesian evidence of a retrieval analysis of the transmission spectrum indicates a preference for a high atmospheric metallicity

[Fe/H] = 2.58(-0.37)(+0.26)

[Fe/H]=2.58-0.37+0.26 and clear skies. The data are also consistent with a lower metallicity composition [Fe/H] < 1.75 and a cloud deck between 10(-2.2) and 10(-5.1) bar, but with weaker Bayesian preference. We retrieve a low CH4 abundance of <10(-4) volume fraction within 1 sigma and <2 x 10(-1) volume fraction within 3<sigma>. We cannot constrain the equilibrium temperature between theoretically imposed limits of 700 and 1000 K. Further observations are needed to confirm quenching of CH4 with K-zz >= 10(8) cm(2) s(-1). We report indications of Na and K in the VLT/ESPRESSO high-resolution spectrum with substantial Bayesian evidence in combination with HST data.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6361 ISBN Medium
Area Expedition Conference
Notes WOS:000624484900001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1353
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Author Cont, D.; Yan, F.; Reiners, A.; Nortmann, L.; Molaverdikhani, K.; Palle, E.; Stangret, M.; Henning, T.; Ribas, I.; Quirrenbach, A.; Caballero, J.A.; Osorio, M.R.Z.; Amado, P.J.; Aceituno, J.; Casasayas-Barris, N.; Czesla, S.; Kaminski, A.; Lopez-Puertas, M.; Montes, D.; Morales, J.C.; Morello, G.; Nagel, E.; Sanchez-Lopez, A.; Sedaghati, E.; Zechmeister, M.
Title Silicon in the dayside atmospheres of two ultra-hot Jupiters Type
Year 2022 Publication Astronomy & Astrophysics Abbreviated Journal Astron. Astrophys.
Volume 657 Issue Pages L2
Keywords planets and satellites: atmospheres; techniques: spectroscopic; planets and satellites: individual: WASP-33b; planets and satellites: individual: KELT-20b/MASCARA-2b
Abstract Atmospheres of highly irradiated gas giant planets host a large variety of atomic and ionic species. Here we observe the thermal emission spectra of the two ultra-hot Jupiters WASP-33b and KELT-20b /MASCARA-2b in the near-infrared wavelength range with CARMENES. Via high-resolution Doppler spectroscopy, we searched for neutral silicon (Si) in their dayside atmospheres. We detect the Si spectral signature of both planets via cross-correlation with model spectra. Detection levels of 4.8 sigma and 5.4 sigma, respectively, are observed when assuming a solar atmospheric composition. This is the first detection of Si in exoplanet atmospheres. The presence of Si is an important finding due to its fundamental role in cloud formation and, hence, for the planetary energy balance. Since the spectral lines are detected in emission, our results also confirm the presence of an inverted temperature profile in the dayside atmospheres of both planets.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6361 ISBN Medium
Area Expedition Conference
Notes WOS:000740006300008 Approved
Call Number UAI @ alexi.delcanto @ Serial 1535
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Author Jenkins, J.S.; Diaz, M.R.; Kurtovic, N.T.; Espinoza, N.; Vines, J.I.; Rojas, P.A.P.; Brahm, R.; Torres, P.; Cortes-Zuleta, P.; Soto, M.G.; Lopez, E.D.; King, G.W.; Wheatley, P.J.; Winn, J.N.; Ciardi, D.R.; Ricker, G.; Vanderspek, R.; Latham, D.W.; Seager, S.; Jenkins, J.M.; Beichman, C.A.; Bieryla, A.; Burke, C.J.; Christiansen, J.L.; Henze, C.E.; Klaus, T.C.; McCauliff, S.; Mori, M.; Narita, N.; Nishiumi, T.; Tamura, M.; de Leon, J.P.; Quinn, S.N.; Villasenor, J.N.; Vezie, M.; Lissauer, J.J.; Collins, K.A.; Collins, K.I.; Isopi, G.; Mallia, F.; Ercolino, A.; Petrovich, C.; Jordan, A.; Acton, J.S.; Armstrong, D.J.; Bayliss, D.; Bouchy, F.; Belardi, C.; Bryant, E.M.; Burleigh, M.R.; Cabrera, J.; Casewell, S.L.; Chaushev, A.; Cooke, B.F.; Eigmuller, P.; Erikson, A.; Foxell, E.; Gansicke, B.T.; Gill, S.; Gillen, E.; Gunther, M.N.; Goad, M.R.; Hooton, M.J.; Jackman, J.A.G.; Louden, T.; McCormac, J.; Moyano, M.; Nielsen, L.D.; Pollacco, D.; Queloz, D.; Rauer, H.; Raynard, L.; Smith, A.M.S.; Tilbrook, R.H.; Titz-Weider, R.; Turner, O.; Udry, S.; Walker, S.R.; Watson, C.A.; West, R.G.; Palle, E.; Ziegler, C.; Law, N.; Mann, A.W.
Title An ultrahot Neptune in the Neptune desert Type
Year 2020 Publication Nature Astronomy Abbreviated Journal Nat. Astron.
Volume 4 Issue 12 Pages 11481157
Keywords PLANETS; ATMOSPHERE; EXOPLANETS; ALGORITHM; EFFICIENT; DWARFS; STARS; TOOL
Abstract About 1 out of 200 Sun-like stars has a planet with an orbital period shorter than one day: an ultrashort-period planet(1,2). All of the previously known ultrashort-period planets are either hot Jupiters, with sizes above 10 Earth radii (R-circle plus), or apparently rocky planets smaller than 2 R-circle plus. Such lack of planets of intermediate size (the `hot Neptune desert') has been interpreted as the inability of low-mass planets to retain any hydrogen/ helium (H/He) envelope in the face of strong stellar irradiation. Here we report the discovery of an ultrashort-period planet with a radius of 4.6 R-circle plus and a mass of 29 M-circle plus, firmly in the hot Neptune desert. Data from the Transiting Exoplanet Survey Satellite(3) revealed transits of the bright Sun-like star LTT 9779 every 0.79 days. The planet's mean density is similar to that of Neptune, and according to thermal evolution models, it has a H/He-rich envelope constituting 9.0(-2.9)(+2.7) % of the total mass. With an equilibrium temperature around 2,000 K, it is unclear how this `ultrahot Neptune' managed to retain such an envelope. Follow-up observations of the planet's atmosphere to better understand its origin and physical nature will be facilitated by the star's brightness (V-mag = 9.8).
Address [Jenkins, James S.; Diaz, Matias R.; Kurtovic, Nicolas T.; Vines, Jose I.; Rojas, Pablo A. Pena; Cortes-Zuleta, Pia] Univ Chile, Dept Astron, Las Condes, Chile, Email: jjenkins@das.uchile.cl
Corporate Author Thesis
Publisher Nature Research Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2397-3366 ISBN Medium
Area Expedition Conference
Notes WOS:000571722300001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1240
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Author Kirk, J.; Rackham, B.V.; MacDonald, R.J.; Lopez-Morales, M.; Espinoza, N.; Lendl, M.; Wilson, J.; D.J.; Wheatley, P.J.; Skillen, I.; Apai, D.; Bixel, A.; Gibson, N.P.; Jordan, A.; Lewis, N.K.; Louden, T.; McGruder, C.D.; Nikolov, N.; Rodler, F.; Weaver, I.C.
Title ACCESS and LRG-BEASTS: A Precise New Optical Transmission Spectrum of the Ultrahot Jupiter WASP-103b Type
Year 2021 Publication Astronomical Journal Abbreviated Journal Astron. J.
Volume 162 Issue 1 Pages 34
Keywords GAS-GIANT EXOPLANET; HOT JUPITERS; ATMOSPHERES; TRANSIT; PLANET; EFFICIENT; SPECTROSCOPY; RETRIEVAL; CHEMISTRY; EXPLAIN
Abstract We present a new ground-based optical transmission spectrum of the ultrahot Jupiter WASP-103b (Teq=2484
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6256 ISBN Medium
Area Expedition Conference
Notes WOS:000667942900001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1434
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Author Schlecker, M.; Kossakowski, D.; Brahm, R.; Espinoza, N.; Henning, T.; Carone, L.; Molaverdikhani, K.; Trifonov, T.; Molliere, P.; Hobson, MJ.; Jordan, A.; Rojas, FI.; Klahr, H.; Sarkis, P.; Bakos, GA.; Bhatti, W.; Osip, D.; Suc, V.; Ricker, G.; Vanderspek, R.; Latham, DW.; Seager, S.; Winn, JN.; Jenkins, JM.; Vezie, M.; Villasenor, JN.; Rose, ME.; Rodriguez, DR.; Rodriguez, JE.; Quinn, SN.; Shporer, A.
Title A highly eccentric warm jupiter orbiting TIC 237913194 Type
Year 2020 Publication Astronomical Journal Abbreviated Journal Astron. J.
Volume 160 Issue 6 Pages 275
Keywords Exoplanet astronomy; Transit photometry; Radial velocity; Exoplanet dynamics; Exoplanet atmospheres; Exoplanet structure; Hot Jupiters; Extrasolar gas giants
Abstract The orbital parameters of warm Jupiters serve as a record of their formation history, providing constraints on formation scenarios for giant planets on close and intermediate orbits. Here, we report the discovery of TIC.237913194b, detected in full-frame images from Sectors 1 and 2 of the Transiting Exoplanet Survey Satellite (TESS), ground-based photometry (Chilean-Hungarian Automated Telescope, Las Cumbres Observatory Global Telescope), and Fiber-fed Extended Range Optical Spectrograph radial velocity time series. We constrain its mass to M-P = 1.942(-0.091)(+0.091) M-J and its radius to R-P = 1.117(-0.047)(+0.054) R-J, implying a bulk density similar to Neptune's. It orbits a G-type star (M-* = 1.026(-0.055)(+0.057) M-circle dot, V = 12.1 mag) with a period of 15.17 days on one of the most eccentric orbits of all known warm giants (e approximate to 0.58). This extreme dynamical state points to a past interaction with an additional, undetected massive companion. A tidal evolution analysis showed a large tidal dissipation timescale, suggesting that the planet is not a progenitor for a hot Jupiter caught during its high-eccentricity migration. TIC.237913194b further represents an attractive opportunity to study the energy deposition and redistribution in the atmosphere of a warm Jupiter with high eccentricity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6256 ISBN Medium
Area Expedition Conference
Notes Approved
Call Number UAI @ alexi.delcanto @ Serial 1286
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Author Sedaghati, E.; MacDonald, R.J.; Casasayas-Barris, N.; Hoeijmakers, H.J.; Boffin, H.M.J.; Rodler, F.; Brahm, R.; Jones, M.; Sanchez-Lopez, A.; Carleo, I.; Figueira, P.; Mehner, A.; Lopez-Puertas, M.
Title A spectral survey of WASP-19b with ESPRESSO Type
Year 2021 Publication Monthly Notices Of The Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.
Volume 505 Issue 1 Pages 435-458
Keywords methods: data analysis; techniques: spectroscopic; planets and satellites: atmospheres; planets and satellites: individual: WASP-19b; stars: activity; stars: individual: WASP-19
Abstract High-resolution precision spectroscopy provides a multitude of robust techniques for probing exoplanetary atmospheres. We present multiple VLT/ESPRESSO transit observations of the hot-Jupiter exoplanet WASP-19b with previously published but disputed atmospheric features from low resolution studies. Through spectral synthesis and modelling of the Rossiter-McLaughlin (RM) effect we calculate stellar, orbital and physical parameters for the system. From narrow-band spectroscopy we do not detect any of Hi, Fei, Mgi, Cai, Nai, and Ki neutral species, placing upper limits on their line contrasts. Through cross-correlation analyses with atmospheric models, we do not detect Fei and place a 3 sigma upper limit of on its mass fraction, from injection and retrieval. We show the inability to detect the presence of H2O for known abundances, owing to lack of strong absorption bands, as well as relatively low S/N ratio. We detect a barely significant peak (3.02 +/- 0.15 sigma) in the cross-correlation map for TiO, consistent with the sub-solar abundance previously reported. This is merely a hint for the presence of TiO and does not constitute a confirmation. However, we do confirm the presence of previously observed enhanced scattering towards blue wavelengths, through chromatic RM measurements, pointing to a hazy atmosphere. We finally present a reanalysis of low-resolution transmission spectra of this exoplanet, concluding that unocculted starspots alone cannot explain previously detected features. Our reanalysis of the FORS2 spectra of WASP-19b finds a similar to 100x sub-solar TiO abundance, precisely constrained to , consistent with the TiO hint from ESPRESSO. We present plausible paths to reconciliation with other seemingly contradicting results.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0035-8711 ISBN Medium
Area Expedition Conference
Notes WOS:000671453100031 Approved
Call Number UAI @ alexi.delcanto @ Serial 1438
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Author Sedaghati, E.; Sanchez-Lopez, A.; Czesla, S.; Lopez-Puertas, M.; Amado, P.J.; Palle, E.; Molaverdikhani, K.; Caballero, J.A.; Nortmann, L.; Quirrenbach, A.; Reiners, A.; Ribas, I.
Title Moderately misaligned orbit of the warm sub-Saturn HD 332231 b Type
Year 2022 Publication Astronomy & Astrophysics Abbreviated Journal Astron. Astrophys.
Volume 659 Issue Pages A44
Keywords planets and satellites: individual: HD 332231b; planets and satellites: atmospheres; methods: observational; techniques: spectroscopic; techniques: radial velocities
Abstract Measurements of exoplanetary orbital obliquity angles for different classes of planets are an essential tool in testing various planet formation theories. Measurements for those transiting planets on relatively large orbital periods (P > 10 d) present a rather difficult observational challenge. Here we present the obliquity measurement for the warm sub-Saturn planet HD 332231 b, which was discovered through Transiting Exoplanet Survey Satellite photometry of sectors 14 and 15, on a relatively large orbital period (18.7 d). Through a joint analysis of previously obtained spectroscopic data and our newly obtained CARMENES transit observations, we estimated the spin-orbit misalignment angle, lambda to be -42.0(-10.6)(+11.3) deg, which challenges Laplacian ideals of planet formation. Through the addition of these new radial velocity data points obtained with CARMENES, we also derived marginal improvements on other orbital and bulk parameters for the planet, as compared to previously published values. We showed the robustness of the obliquity measurement through model comparison with an aligned orbit. Finally, we demonstrated the inability of the obtained data to probe any possible extended atmosphere of the planet, due to a lack of precision, and place the atmosphere in the context of a parameter detection space.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6361 ISBN Medium
Area Expedition Conference
Notes WOS:000763639300002 Approved
Call Number UAI @ alexi.delcanto @ Serial 1548
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Author Weaver, IC.; Lopez-Morales, M.; Alam, MK.; Espinoza, N.; Rackham, BV.; Goyal, JM.; MacDonald, RJ.; Lewis, NK.; Apai, D.; Bixel, A.; Jordan, A.; Kirk, J.; McGruder, C.; Osip, DJ.
Title ACCESS: An Optical Transmission Spectrum of the High-gravity Hot Jupiter HAT-P-23b Type
Year 2021 Publication Astronomical Journal Abbreviated Journal Astron. J.
Volume 161 Issue 6 Pages 278
Keywords EXOPLANET HD 189733B; HST PANCET PROGRAM; EXTRASOLAR PLANET; CLOUDY ATMOSPHERE; CLEAR ATMOSPHERE; GIANT PLANET; WATER-VAPOR; GAS GIANT; SPECTROSCOPY; HUBBLE
Abstract We present a new ground-based visible transmission spectrum of the high-gravity, hot Jupiter HAT-P-23b, obtained as part of the ACCESS project. We derive the spectrum from five transits observed between 2016 and 2018, with combined wavelength coverage between 5200 angstrom and 9269 angstrom in 200 angstrom bins, and with a median precision of 247 ppm per bin. HAT-P-23b's relatively high surface gravity (g approximate to 30 m s(-2)), combined with updated stellar and planetary parameters from Gaia DR2, gives a five-scale-height signal of 384 ppm for a hydrogen-dominated atmosphere. Bayesian models favor a clear atmosphere for the planet with the tentative presence of TiO, after simultaneously modeling stellar contamination, using spots parameter constraints from photometry. If confirmed, HAT-P-23b would be the first example of a high-gravity gas giant with a clear atmosphere observed in transmission at optical/near-IR wavelengths; therefore, we recommend expanding observations to the UV and IR to confirm our results and further characterize this planet. This result demonstrates how combining transmission spectroscopy of exoplanet atmospheres with long-term photometric monitoring of the host stars can help disentangle the exoplanet and stellar activity signals.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6256 ISBN Medium
Area Expedition Conference
Notes WOS:000655343200001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1396
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Author Yan, F.; Espinoza, N.; Molaverdikhani, K.; Henning, T.; Mancini, L.; Mallonn, M.; Rackham, B.V.; Apai, D.; Jordan, A.; Molliere, P.; Chen, G.; Carone, L.; Reiners, A.
Title LBT transmission spectroscopy of HAT-P-12b: Confirmation of a cloudy atmosphere with no significant alkali features Type
Year 2020 Publication Astronomy & Astrophysics Abbreviated Journal Astron. Astrophys.
Volume 642 Issue Pages 13 pp
Keywords planets and satellites: atmospheres; techniques: spectroscopic; stars: atmospheres; planets and satellites: individual: HAT-P-12b
Abstract The hot sub-Saturn-mass exoplanet HAT-P-12b is an ideal target for transmission spectroscopy because of its inflated radius. We observed one transit of the planet with the multi-object double spectrograph (MODS) on the Large Binocular Telescope (LBT) with the binocular mode and obtained an atmosphere transmission spectrum with a wavelength coverage of similar to 0.4-0.9 μm. The spectrum is relatively flat and does not show any significant sodium or potassium absorption features. Our result is consistent with the revised Hubble Space Telescope (HST) transmission spectrum of a previous work, except that the HST result indicates a tentative detection of potassium. The potassium discrepancy could be the result of statistical fluctuation of the HST dataset. We fit the planetary transmission spectrum with an extensive grid of cloudy models and confirm the presence of high-altitude clouds in the planetary atmosphere. The fit was performed on the combined LBT and HST spectrum, which has an overall wavelength range of 0.4-1.6 μm. The LBT/MODS spectrograph has unique advantages in transmission spectroscopy observations because it can cover a wide wavelength range with a single exposure and acquire two sets of independent spectra simultaneously.
Address [Yan, F.; Reiners, A.] Georg August Univ, Inst Astrophys, Friedrich Hund Pl 1, D-37077 Gottingen, Germany, Email: fei.yan@uni-goettingen.de
Corporate Author Thesis
Publisher Edp Sciences S A Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1432-0746 ISBN Medium
Area Expedition Conference
Notes WOS:000581918600001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1237
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