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1. TOI-1801 b: A temperate mini-Neptune around a young M0.5 dwarf

Author

Mallorquín, M., Goffo, E., Pallé, E., Lodieu, N., Béjar, V. J. S., Isaacson, H., Osorio, M. R. Zapatero, Dreizler, S., Stock, S., Luque, R., Murgas, F., Peña, L., Sanz-Forcada, J., Morello, G., Ciardi, D. R., Furlan, E., Collins, K. A., Herrero, E., Vanaverbeke, S., Plavchan, P., Narita, N., Schweitzer, A., Pérez-Torres, M., Quirrenbach, A., Kemmer, J., Hatzes, A. P., Howard, A., Schlecker, M., Reffert, S., Nagel, E., Morales, J. C., Orell-Miquel, J., Duque-Arribas, C., Carleo, I., Cifuentes, C., Nowak, G., Ribas, I., Reiners, A., Amado, P. J., Caballero, J. A., Henning, Th., Pinter, V., Murphy, J. M. Akana, Beard, C., Blunt, S., Brinkman, C. L., Cale, B., Chontos, A., Collins, K. I., Crossfield, I. J. M., Dai, F., Dalba, P. A., Dufoer, S., Mufti, M. El, Espinoza, N., Fetherolf, T., Fukui, A., Giacalone, S., Gnilka, C., Gonzales, E., Grunblatt, S. K., Howell, S., Huber, D., Kane, S. R., de León, J. P., Lubin, J., MacDougall, M. G., Massey, B., Montes, D., Mori, M., Parviainen, H., Passegger, V. M., Polanski, A. S., Robertson, P., Schwarz, R. P., Srdoc, G., Tabernero, H. M., Tanner, A., Turtelboom, E., Van Zandt, J., Weiss, L., and Zechmeister, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery, mass, and radius determination of TOI-1801 b, a temperate mini-Neptune around a young M dwarf. TOI-1801 b was observed in TESS sectors 22 and 49, and the alert that this was a TESS planet candidate with a period of 21.3 days went out in April 2020. However, ground-based follow-up observations, including seeing-limited photometry in and outside transit together with precise radial velocity (RV) measurements with CARMENES and HIRES revealed that the true period of the planet is 10.6 days. These observations also allowed us to retrieve a mass of 5.74 $\pm$ 1.46 $M_\oplus$, which together with a radius of 2.08 $\pm$ 0.12 $R_\oplus$, means that TOI-1801 b is most probably composed of water and rock, with an upper limit of 2\% by mass of H$_{2}$ in its atmosphere. The stellar rotation period of 16 days is readily detectable in our RV time series and in the ground-based photometry. We derived a likely age of 600--800 Myr for the parent star TOI-1801, which means that TOI-1801 b is the least massive young mini-Neptune with precise mass and radius determinations. Our results suggest that if TOI-1801 b had a larger atmosphere in the past, it must have been removed by some evolutionary mechanism on timescales shorter than 1 Gyr., Comment: Accepted in A&A. 29 pages, 21 figures

Published
2023
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2. Planetary companions orbiting the M dwarfs GJ 724 and GJ 3988. A CARMENES and IRD collaboration

Author

Gorrini, P., Kemmer, J., Dreizler, S., Burn, R., Hirano, T., Pozuelos, F. J., Kuzuhara, M., Caballero, J. A., Amado, P. J., Harakawa, H., Kudo, T., Quirrenbach, A., Reiners, A., Ribas, I., Béjar, V. J. S., Chaturvedi, P., Cifuentes, C., Galadí-Enríquez, D., Hatzes, A. P., Kaminski, A., Kotani, T., Kürster, M., Livingston, J. H., González, M. J. López, Montes, D., Morales, J. C., Murgas, F., Omiya, M., Pallé, E., Rodríguez, E., Sato, B., Schweitzer, A., Shan, Y., Takarada, T., Tal-Or, L., Tamura, M., Vievard, S., Osorio, M. R. Zapatero, and Zechmeister, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of two exoplanets around the M dwarfs GJ 724 and GJ 3988 using the radial velocity (RV) method. We obtained a total of 153 3.5 m Calar Alto/CARMENES spectra for both targets and measured their RVs and activity indicators. We also added archival ESO/HARPS data for GJ 724 and infrared RV measurements from Subaru/IRD for GJ 3988. We searched for periodic and stable signals to subsequently construct Keplerian models, considering different numbers of planets, and we selected the best models based on their Bayesian evidence. Gaussian process (GP) regression was included in some models to account for activity signals. For both systems, the best model corresponds to one single planet. The minimum masses are $10.75^{+0.96}_{-0.87}$ and $3.69^{+0.42}_{-0.41}$ Earth-masses for GJ 724 b and GJ 3988 b, respectively. Both planets have short periods (P < 10 d) and, therefore, they orbit their star closely (a < 0.05 au). GJ 724 b has an eccentric orbit (e = $0.577^{+0.055}_{-0.052}$), whereas the orbit of GJ 3988 b is circular. The high eccentricity of GJ 724 b makes it the most eccentric single exoplanet (to this date) around an M dwarf. Thus, we suggest a further analysis to understand its configuration in the context of planetary formation and architecture. In contrast, GJ 3988 b is an example of a common type of planet around mid-M dwarfs., Comment: A&A in press

Published
2023
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3. The CARMENES search for exoplanets around M dwarfs. A sub-Neptunian mass planet in the habitable zone of HN Lib

Author

González-Álvarez, E., Kemmer, J., Chaturvedi, P., Caballero, J. A., Quirrenbach, A., Amado, P. J., Béjar, V. J. S., Cifuentes, C., Herrero, E., Kossakowski, D., Reiners, A., Ribas, I., Rodríguez, E., Rodríguez-López, C., Sanz-Forcada, J., Shan, Y., Stock, S., Tabernero, H. M., Tal-Or, L., Osorio, M. R. Zapatero, Hatzes, A. P., Henning, Th., López-González, M. J., Montes, D., Morales, J. C., Pallé, E., Pedraz, S., Perger, M., Reffert, S., Sabotta, S., Schweitzer, A., and Zechmeister, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of HN Lib b, a sub-Neptunian mass planet orbiting the nearby ($d \approx$ = 6.25 pc) M4.0 V star HN Lib detected by our CARMENES radial-velocity (RV) survey. We determined a planetary minimum mass of $M_\text{b}\sin i = $ 5.46 $\pm$ 0.75 $\text{M}_\oplus$ and an orbital period of $P_\text{b} = $ 36.116 $\pm$ 0.029 d, using $\sim$5 yr of CARMENES data, as well as archival RVs from HARPS and HIRES spanning more than 13 years. The flux received by the planet equals half the instellation on Earth, which places it in the middle of the conservative habitable zone (HZ) of its host star. The RV data show evidence for another planet candidate with $M_\text{[c]}\sin i = $ 9.7 $\pm$ 1.9 $\text{M}_\oplus$ and $P_\text{[c]} = $ 113.46 $\pm$ 0.20 d. The long-term stability of the signal and the fact that the best model for our data is a two-planet model with an independent activity component stand as strong arguments for establishing a planetary origin. However, we cannot rule out stellar activity due to its proximity to the rotation period of HN Lib, which we measured using CARMENES activity indicators and photometric data from a ground-based multi-site campaign as well as archival data. The discovery adds HN Lib b to the shortlist of super-Earth planets in the habitable zone of M dwarfs, but HN Lib [c] probably cannot be inhabited because, if confirmed, it would most likely be an icy giant.

Published
2023
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4. The CARMENES search for exoplanets around M dwarfs. Guaranteed time observations Data Release 1 (2016-2020)

Author

Ribas, I., Reiners, A., Zechmeister, M., Caballero, J. A., Morales, J. C., Sabotta, S., Baroch, D., Amado, P. J., Quirrenbach, A., Abril, M., Aceituno, J., Anglada-Escudé, G., Azzaro, M., Barrado, D., Béjar, V. J. S., de Haro, D. Benítez, Bergond, G., Bluhm, P., Ortega, R. Calvo, Guillén, C. Cardona, Chaturvedi, P., Cifuentes, C., Colomé, J., Cont, D., Cortés-Contreras, M., Czesla, S., Díez-Alonso, E., Dreizler, S., Duque-Arribas, C., Espinoza, N., Fernández, M., Fuhrmeister, B., Galadí-Enríquez, D., García-López, A., González-Álvarez, E., Hernández, J. I. González, Guenther, E. W., de Guindos, E., Hatzes, A. P., Henning, Th., Herrero, E., Hintz, D., Huelmo, Á. L., Jeffers, S. V., Johnson, E. N., de Juan, E., Kaminski, A., Kemmer, J., Khaimova, J., Khalafinejad, S., Kossakowski, D., Kürster, M., Labarga, F., Lafarga, M., Lalitha, S., Lampón, M., Lillo-Box, J., Lodieu, N., González, M. J. López, López-Puertas, M., Luque, R., Magán, H., Mancini, L., Marfil, E., Martín, E. L., Martín-Ruiz, S., Molaverdikhani, K., Montes, D., Nagel, E., Nortmann, L., Nowak, G., Pallé, E., Passegger, V. M., Pavlov, A., Pedraz, S., Perdelwitz, V., Perger, M., Ramón-Ballesta, A., Reffert, S., Revilla, D., Rodríguez, E., Rodríguez-López, C., Sadegi, S., Carrasco, M. Á. Sánchez, Sánchez-López, A., Sanz-Forcada, J., Schäfer, S., Schlecker, M., Schmitt, J. H. M. M., Schöfer, P., Schweitzer, A., Seifert, W., Shan, Y., Skrzypinski, S. L., Solano, E., Stahl, O., Stangret, M., Stock, S., Stürmer, J., Tabernero, H. M., Tal-Or, L., Trifonov, T., Vanaverbeke, S., Yan, F., and Osorio, M. R. Zapatero

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

The CARMENES instrument was conceived to deliver high-accuracy radial velocity (RV) measurements with long-term stability to search for temperate rocky planets around a sample of nearby cool stars. The broad wavelength coverage was designed to provide a range of stellar activity indicators to assess the nature of potential RV signals and to provide valuable spectral information to help characterise the stellar targets. The CARMENES Data Release 1 (DR1) makes public all observations obtained during the CARMENES guaranteed time observations, which ran from 2016 to 2020 and collected 19,633 spectra for a sample of 362 targets. The CARMENES survey target selection was aimed at minimising biases, and about 70% of all known M dwarfs within 10 pc and accessible from Calar Alto were included. The data were pipeline-processed, and high-level data products, including 18,642 precise RVs for 345 targets, were derived. Time series data of spectroscopic activity indicators were also obtained. We discuss the characteristics of the CARMENES data, the statistical properties of the stellar sample, and the spectroscopic measurements. We show examples of the use of CARMENES data and provide a contextual view of the exoplanet population revealed by the survey, including 33 new planets, 17 re-analysed planets, and 26 confirmed planets from transiting candidate follow-up. A subsample of 238 targets was used to derive updated planet occurrence rates, yielding an overall average of 1.44+/-0.20 planets with 1 M_Earth < M sin i < 1000 M_Earth and 1 d < P_orb < 1000 d per star, and indicating that nearly every M dwarf hosts at least one planet. CARMENES data have proven very useful for identifying and measuring planetary companions as well as for additional applications, such as the determination of stellar properties, the characterisation of stellar activity, and the study of exoplanet atmospheres., Comment: Published in A&A (https://www.aanda.org/10.1051/0004-6361/202244879), 25 pages, 12 figures, Tables 1 and 2 only available online

Published
2023
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5. The CARMENES search for exoplanets around M dwarfs, Wolf 1069 b: Earth-mass planet in the habitable zone of a nearby, very low-mass star

Author

Kossakowski, D., Kürster, M., Trifonov, T., Henning, Th., Kemmer, J., Caballero, J. A., Burn, R., Sabotta, S., Crouse, J. S., Fauchez, T. J., Nagel, E., Kaminski, A., Herrero, E., Rodríguez, E., González-Álvarez, E., Quirrenbach, A., Amado, P. J., Ribas, I., Reiners, A., Aceituno, J., Béjar, V. J. S., Baroch, D., Bastelberger, S. T., Chaturvedi, P., Cifuentes, C., Dreizler, S., Jeffers, S. V., Kopparapu, R., Lafarga, M., López-González, M. J., n-Ruiz, S. Martí, Montes, D., Morales, J. C., Pallé, E., Pavlov, A., Pedraz, S., Perdelwitz, V., Pérez-Torres, M., Perger, M., Reffert, S., López, C. Rodríguez, Schlecker, M., Schöfer, P., Schweitzer, A., Shan, Y., Shields, A., Stock, S., Wolf, E., Osorio, M. R. Zapatero, and Zechmeister, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

We present the discovery of an Earth-mass planet ($M_b\sin i = 1.26\pm0.21M_\oplus$) on a 15.6d orbit of a relatively nearby ($d\sim$9.6pc) and low-mass ($0.167\pm0.011 M_\odot$) M5.0V star, Wolf 1069. Sitting at a separation of $0.0672\pm0.0014$au away from the host star puts Wolf 1069b in the habitable zone (HZ), receiving an incident flux of $S=0.652\pm0.029S_\oplus$. The planetary signal was detected using telluric-corrected radial-velocity (RV) data from the CARMENES spectrograph, amounting to a total of 262 spectroscopic observations covering almost four years. There are additional long-period signals in the RVs, one of which we attribute to the stellar rotation period. This is possible thanks to our photometric analysis including new, well-sampled monitoring campaigns undergone with the OSN and TJO facilities that supplement archival photometry (i.e., from MEarth and SuperWASP), and this yielded an updated rotational period range of $P_{rot}=150-170$d, with a likely value at $169.3^{+3.7}_{-3.6}$d. The stellar activity indicators provided by the CARMENES spectra likewise demonstrate evidence for the slow rotation period, though not as accurately due to possible factors such as signal aliasing or spot evolution. Our detectability limits indicate that additional planets more massive than one Earth mass with orbital periods of less than 10 days can be ruled out, suggesting that perhaps Wolf 1069 b had a violent formation history. This planet is also the 6th closest Earth-mass planet situated in the conservative HZ, after Proxima Centauri b, GJ 1061d, Teegarden's Star c, and GJ 1002 b and c. Despite not transiting, Wolf 1069b is nonetheless a very promising target for future three-dimensional climate models to investigate various habitability cases as well as for sub-ms$^{-1}$ RV campaigns to search for potential inner sub-Earth-mass planets in order to test planet formation theories., Comment: 26 pages, 15 figures

Published
2023
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6. The CARMENES search for exoplanets around M dwarfs: Stable radial-velocity variations at the rotation period of AD~Leonis -- A test case study of current limitations to treating stellar activity

Author

Kossakowski, D., Kürster, M., Henning, Th., Trifonov, T., Caballero, J. A., Lafarga, M., Bauer, F. F., Stock, S., Kemmer, J., Jeffers, S. V., Amado, P. J., Pérez-Torres, M., Béjar, V. J. S., Cortés-Contreras, M., Ribas, I., Reiners, A., Quirrenbach, A., Aceituno, J., Baroch, D., Cifuentes, C., Dreizler, S., Forcada, J. S., Hatzes, A., Kaminski, A., Montes, D., Morales, J. C., Pavlov, A., Peña, L., Perdelwitz, V., Reffert, S., Revilla, D., López, C. Rodríguez, Rosich, A., Sadegi, S., Schöfer, P., Schweitzer, A., and Zechmeister, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

Context: A challenge with radial-velocity (RV) data is disentangling the origin of signals either due to a planetary companion or to stellar activity. In fact, the existence of a planetary companion has been proposed, as well as contested, around the relatively bright, nearby M3.0V star AD Leo at the same period as the stellar rotation of 2.23d. Aims: We further investigate the nature of this signal. We introduce new CARMENES optical and near-IR RV data and an analysis in combination with archival data taken by HIRES and HARPS, along with more recent data from HARPS-N, GIANO-B, and HPF. Also, we address the confusion concerning the binarity of AD Leo. Methods: We consider possible correlations between the RVs and various stellar activity indicators accessible with CARMENES. We applied models within a Bayesian framework to determine whether a Keplerian model, a red-noise quasi-periodic model using a Gaussian process, or a mixed model would explain the observed data best. We also exclusively focus on spectral lines potentially associated with stellar activity. Results: The CARMENES RV data agree with the previously reported periodicity of 2.23d, correlate with some activity indicators, and exhibit chromaticity. However, when considering the entire RV data set, we find that a mixed model composed of a stable and a variable component performs best. Moreover, when recomputing the RVs using only spectral lines insensitive to activity, there appears to be some residual power at the period of interest. We therefore conclude that it is not possible to determinedly prove that there is no planet orbiting in synchronization with the stellar rotation given our data, current tools, machinery, and knowledge of how stellar activity affects RVs. We do rule out planets more massive than 27M_E (=0.084M_J). We also exclude any binary companion around AD Leo with Msini > 3-6M_J on orbital periods <14yr., Comment: 27 pages, 11 figures

Published
2022
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7. The HD 260655 system: Two rocky worlds transiting a bright M dwarf at 10 pc

Author

Luque, R., Fulton, B. J., Kunimoto, M., Amado, P. J., Gorrini, P., Dreizler, S., Hellier, C., Henry, G. W., Molaverdikhani, K., Morello, G., Peña-Moñino, L., Pérez-Torres, M., Pozuelos, F. J., Shan, Y., Anglada-Escudé, G., Béjar, V. J. S., Bergond, G., Boyle, A. W., Caballero, J. A., Charbonneau, D., Ciardi, D. R., Dufoer, S., Espinoza, N., Everett, M., Fischer, D., Hatzes, A. P., Henning, Th., Hesse, K., Howard, A., Howell, S. B., Isaacson, H., Jeffers, S. V., Jenkins, J. M., Kane, S. R., Kemmer, J., Khalafinejad, S., Kidwell Jr., R. C., Kossakowski, D., Latham, D. W., Lillo-Box, J., Lissauer, J. J., Montes, D., Orell-Miquel, J., Pallé, E., Pollacco, D., Quirrenbach, A., Reffert, S., Reiners, A., Ribas, I., Ricker, G. R., Rogers, L. A., Sanz-Forcada, J., Schlecker, M., Schweitzer, A., Seager, S., Shporer, A., Stassun, K. G., Stock, S., Tal-Or, L., Ting, E. B., Trifonov, T., Vanaverbeke, S., Vanderspek, R., Villaseñor, J., Winn, J. N., Winters, J. G., and Osorio, M. R. Zapatero

Subjects
Astrophysics - Earth and Planetary Astrophysics, Physics - Space Physics
Abstract

We report the discovery of a multi-planetary system transiting the M0 V dwarf HD 260655 (GJ 239, TOI-4599). The system consists of at least two transiting planets, namely HD 260655 b, with a period of 2.77 d, a radius of R$_b$ = 1.240$\pm$0.023 R$_\oplus$, a mass of M$_b$ = 2.14$\pm$0.34 M$_\oplus$, and a bulk density of $\rho_b$ = 6.2$\pm$1.0 g cm$^{-3}$, and HD 260655 c, with a period of 5.71 d, a radius of R$_c$ = 1.533$^{+0.051}_{-0.046}$ R$_\oplus$, a mass of M$_c$ = 3.09$\pm$0.48 M$_\oplus$, and a bulk density of $\rho_c$ = 4.7$^{+0.9}_{-0.8}$ g cm$^{-3}$. The planets were detected in transit by the TESS mission and confirmed independently with archival and new precise radial velocities obtained with the HIRES and CARMENES instruments since 1998 and 2016, respectively. At a distance of 10 pc, HD 260655 becomes the fourth closest known multi-transiting planet system after HD 219134, LTT 1445 A, and AU Mic. Due to the apparent brightness of the host star (J = 6.7 mag), both planets are among the most suitable rocky worlds known today for atmospheric studies with the JWST, both in transmission and emission., Comment: 24 pages, 17 figures. Accepted for publication in A&A

Published
2022
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8. Discovery and mass measurement of the hot, transiting, Earth-sized planet GJ 3929 b

Author

Kemmer, J., Dreizler, S., Kossakowski, D., Stock, S., Quirrenbach, A., Caballero, J. A., Amado, P. J., Collins, K. A., Espinoza, N., Herrero, E., Jenkins, J. M., Latham, D. W., Lillo-Box, J., Narita, N., Pallé, E., Reiners, A., Ribas, I., Ricker, G., Rodríguez, E., Seager, S., Vanderspek, R., Wells, R., Winn, J., Aceituno, F. J., Béjar, V. J. S., Barclay, T., Bluhm, P., Chaturvedi, P., Cifuentes, C., Collins, K. I., Cortés-Contreras, M., Demory, B. -O., Fausnaugh, M. M., Fukui, A., Chew, Y. Gómez Maqueo, Galadí-Enríquez, D., Gan, T., Gillon, M., Golovin, A., Hatzes, A. P., Henning, T., Huang, C., Jeffers, S. V., Kaminski, A., Kunimoto, M., Kürster, M., López-González, M. J., Lafarga, M., Luque, R., McCormac, J., Molaverdikhani, K., Montes, D., Morales, J. C., Passegger, V. M., Reffert, S., Sabin, L., Schöfer, P., Schanche, N., Schlecker, M., Schroffenegger, U., Schwarz, R. P., Schweitzer, A., Sota, A., Tenenbaum, P., Trifonov, T., Vanaverbeke, S., and Zechmeister, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of GJ 3929 b, a hot Earth-sized planet orbiting the nearby M3.5 V dwarf star, GJ 3929 (G 180--18, TOI-2013). Joint modelling of photometric observations from TESS sectors 24 and 25 together with 73 spectroscopic observations from CARMENES and follow-up transit observations from SAINT-EX, LCOGT, and OSN yields a planet radius of $R_b = 1.150 +/- 0.040$ R$_{earth}$, a mass of $M_b = 1.21 +/- 0.42$ M$_{earth}$, and an orbital period of $P_b = 2.6162745 +/- 0.0000030$ d. The resulting density of $\rho_b= 4.4 +/- 1.6$ g/cm$^{-3}$ is compatible with the Earth's mean density of about 5.5 g/cm$^{-3}$. Due to the apparent brightness of the host star (J=8.7 mag) and its small size, GJ 3929 b is a promising target for atmospheric characterisation with the JWST. Additionally, the radial velocity data show evidence for another planet candidate with $P_{[c]} = 14.303 +/- 0.035$ d, which is likely unrelated to the stellar rotation period, $P_{rot} = 122+/-13$ d, which we determined from archival HATNet and ASAS-SN photometry combined with newly obtained TJO data., Comment: 24 pages; accepted for publication in A&A

Published
2022
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9. A multi-planetary system orbiting the early-M dwarf TOI-1238

Author

González-Álvarez, E., Osorio, M. R. Zapatero, Sanz-Forcada, J., Caballero, J. A., Reffert, S., Béjar, V. J. S., Hatzes, A. P., Herrero, E., Jeffers, S. V., Kemmer, J., López-González, M. J., Luque, R., Molaverdikhani, K., Morello, G., Nagel, E., Quirrenbach, A., Rodríguez, E., Rodríguez-López, C., Schlecker, M., Schweitzer, A., Stock, S., Passegger, V. M., Trifonov, T., Amado, P. J., Baker, D., Boyd, P. T., Cadieux, C., Charbonneau, D., Collins, K. A., Doyon, R., Dreizler, S., Espinoza, N., Furész, G., Furlan, E., Hesse, K., Howell, S. B., Jenkins, J. M., Kidwell, R. C., Latham, D. W., McLeod, K. K., Montes, D., Morales, J. C., O'Dwyer, T., Pallé, E., Pedraz, S., Reiners, A., Ribas, I., Quinn, S. N., Schnaible, C., Seager, S., Skinner, B., Smith, J. C., Schwarz, R. P., Shporer, A., Vanderspek, R., and Winn, J. N.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Two transiting planet candidates with super-Earth radii around the nearby K7--M0 dwarf star TOI-1238 were announced by TESS. We aim to validate their planetary nature using precise radial velocities (RV) taken with the CARMENES spectrograph. We obtained 55 CARMENES RV data that span 11 months. For a better characterization of the parent star's activity, we also collected contemporaneous optical photometric observations and retrieved archival photometry from the literature. We performed a combined TESS+CARMENES photometric and spectroscopic analysis by including Gaussian processes and Keplerian orbits to account for the stellar activity and planetary signals simultaneously. We estimate that TOI-1238 has a rotation period of 40 $\pm$ 5 d based on photometric and spectroscopic data. The combined analysis confirms the discovery of two transiting planets, TOI-1238 b and c, with orbital periods of $0.764597^{+0.000013}_{-0.000011}$ d and $3.294736^{+0.000034}_{-0.000036}$ d, masses of 3.76$^{+1.15}_{-1.07}$ M$_{\oplus}$ and 8.32$^{+1.90}_{-1.88}$ M$_{\oplus}$, and radii of $1.21^{+0.11}_{-0.10}$ R$_{\oplus}$ and $2.11^{+0.14}_{-0.14}$ R$_{\oplus}$. They orbit their parent star at semimajor axes of 0.0137$\pm$0.0004 au and 0.036$\pm$0.001 au, respectively. The two planets are placed on opposite sides of the radius valley for M dwarfs and lie between the star and the inner border of TOI-1238's habitable zone. The inner super-Earth TOI-1238 b is one of the densest ultra-short-period planets ever discovered ($\rho=11.7^{+4.2}_{-3.4}$ g $\rm cm^{-3}$). The CARMENES data also reveal the presence of an outer, non-transiting, more massive companion with an orbital period and radial velocity amplitude of $\geq$600 d and $\geq$70 m s$^{-1}$, which implies a likely mass of $M \geq 2 \sqrt{1-e^2}$ M$_{\rm Jup}$ and a separation $\geq$1.1 au from its parent star.

Published
2021
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10. CARMENES input catalog of M dwarfs

Author

Shan, Y., primary, Revilla, D., additional, Skrzypinski, S. L., additional, Dreizler, S., additional, Béjar, V. J. S., additional, Caballero, J. A., additional, Cardona Guillén, C., additional, Cifuentes, C., additional, Fuhrmeister, B., additional, Reiners, A., additional, Vanaverbeke, S., additional, Ribas, I., additional, Quirrenbach, A., additional, Amado, P. J., additional, Aceituno, F. J., additional, Casanova, V., additional, Cortés-Contreras, M., additional, Dubois, F., additional, Gorrini, P., additional, Henning, Th., additional, Herrero, E., additional, Jeffers, S. V., additional, Kemmer, J., additional, Lalitha, S., additional, Lodieu, N., additional, Logie, L., additional, López González, M. J., additional, Martín-Ruiz, S., additional, Montes, D., additional, Morales, J. C., additional, Nagel, E., additional, Pallé, E., additional, Perdelwitz, V., additional, Pérez-Torres, M., additional, Pollacco, D., additional, Rau, S., additional, Rodríguez-López, C., additional, Rodríguez, E., additional, Schöfer, P., additional, Seifert, W., additional, Sota, A., additional, Zapatero Osorio, M. R., additional, and Zechmeister, M., additional

Published
2024
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11. Planetary companions orbiting the M dwarfs GJ 724 and GJ 3988. A CARMENES and IRD collaboration

Author

Gorrini, P., primary, Kemmer, J., additional, Dreizler, S., additional, Burn, R., additional, Hirano, T., additional, Pozuelos, F. J., additional, Kuzuhara, M., additional, Caballero, J. A., additional, Amado, P. J., additional, Harakawa, H., additional, Kudo, T., additional, Quirrenbach, A., additional, Reiners, A., additional, Ribas, I., additional, Béjar, V. J. S., additional, Chaturvedi, P., additional, Cifuentes, C., additional, Galadí-Enríquez, D., additional, Hatzes, A. P., additional, Kaminski, A., additional, Kotani, T., additional, Kürster, M., additional, Livingston, J. H., additional, López González, M. J., additional, Montes, D., additional, Morales, J. C., additional, Murgas, F., additional, Omiya, M., additional, Pallé, E., additional, Rodríguez, E., additional, Sato, B., additional, Schweitzer, A., additional, Shan, Y., additional, Takarada, T., additional, Tal-Or, L., additional, Tamura, M., additional, Vievard, S., additional, Zapatero Osorio, M. R., additional, and Zechmeister, M., additional

Published
2023
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12. The CARMENES search for exoplanets around M dwarfs

Author

González-Álvarez, E., primary, Kemmer, J., additional, Chaturvedi, P., additional, Caballero, J. A., additional, Quirrenbach, A., additional, Amado, P. J., additional, Béjar, V. J. S., additional, Cifuentes, C., additional, Herrero, E., additional, Kossakowski, D., additional, Reiners, A., additional, Ribas, I., additional, Rodríguez, E., additional, Rodríguez-López, C., additional, Sanz-Forcada, J., additional, Shan, Y., additional, Stock, S., additional, Tabernero, H. M., additional, Tal-Or, L., additional, Osorio, M. R. Zapatero, additional, Hatzes, A. P., additional, Henning, Th., additional, López-González, M. J., additional, Montes, D., additional, Morales, J. C., additional, Pallé, E., additional, Pedraz, S., additional, Perger, M., additional, Reffert, S., additional, Sabotta, S., additional, Schweitzer, A., additional, and Zechmeister, M., additional

Published
2023
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14. The CARMENES search for exoplanets around M dwarfs. A sub-Neptunian mass planet in the habitable zone of HN Lib

Author

Ministerio de Ciencia e Innovación (España), European Commission, González-Álvarez, E., Kemmer, J., Chaturvedi, P., Caballero, J. A., Quirrenbach, Andreas, Amado, Pedro J., Béjar, Victor J. S., Cifuentes, C., Herrero, E., Kossakowski, D., Reiners, Ansgar, Ribas, Ignasi, Rodríguez Martínez, Eloy, Rodríguez López, C., Sanz-Forcada, J., Shan, Y., Stock, S., Tabernero, H. M., Tal-Or, L., Zapatero Osorio, María Rosa, Hatzes, Artie P., Henning, Thomas, López González, Maria J., Montes, D., Morales, Juan Carlos, Pallé, Enric, Pedraz, S., Perger, M., Reffert, S., Sabotta, S., Schweitzer, Andreas, Zechmeister, Mathias, Ministerio de Ciencia e Innovación (España), European Commission, González-Álvarez, E., Kemmer, J., Chaturvedi, P., Caballero, J. A., Quirrenbach, Andreas, Amado, Pedro J., Béjar, Victor J. S., Cifuentes, C., Herrero, E., Kossakowski, D., Reiners, Ansgar, Ribas, Ignasi, Rodríguez Martínez, Eloy, Rodríguez López, C., Sanz-Forcada, J., Shan, Y., Stock, S., Tabernero, H. M., Tal-Or, L., Zapatero Osorio, María Rosa, Hatzes, Artie P., Henning, Thomas, López González, Maria J., Montes, D., Morales, Juan Carlos, Pallé, Enric, Pedraz, S., Perger, M., Reffert, S., Sabotta, S., Schweitzer, Andreas, and Zechmeister, Mathias

Abstract

We report the discovery of HN Lib b, a sub-Neptunian mass planet orbiting the nearby (d ≈ = 6.25 pc) M4.0 V star HN Lib detected by our CARMENES radial-velocity (RV) survey. We determined a planetary minimum mass of Mb sin i = 5.46 ± 0.75 M⊕ and an orbital period of Pb = 36.116 ± 0.029 d, using ~5 yr of CARMENES data, as well as archival RVs from HARPS and HIRES spanning more than 13 yr. The flux received by the planet equals half the instellation on Earth, which places it in the middle of the conservative habitable zone (HZ) of its host star. The RV data show evidence for another planet candidate with M[c] sin i = 9.7 ± 1.9 M⊕ and P[c] = 113.46 ± 0.20 d. The long-term stability of the signal and the fact that the best model for our data is a two-planet model with an independent activity component stand as strong arguments for establishing a planetary origin. However, we cannot rule out stellar activity due to its proximity to the rotation period of HN Lib, which we measured using CARMENES activity indicators and photometric data from a ground-based multi-site campaign as well as archival data. The discovery adds HN Lib b to the shortlist of super-Earth planets in the habitable zone of M dwarfs, but HN Lib [c] probably cannot be inhabited because, if confirmed, it would most likely be an icy giant. © The Authors 2023.

Published
2023

15. The CARMENES search for exoplanets around M dwarfs

Author

Kossakowski, D., primary, Kürster, M., additional, Trifonov, T., additional, Henning, Th., additional, Kemmer, J., additional, Caballero, J. A., additional, Burn, R., additional, Sabotta, S., additional, Crouse, J. S., additional, Fauchez, T. J., additional, Nagel, E., additional, Kaminski, A., additional, Herrero, E., additional, Rodríguez, E., additional, González-Álvarez, E., additional, Quirrenbach, A., additional, Amado, P. J., additional, Ribas, I., additional, Reiners, A., additional, Aceituno, J., additional, Béjar, V. J. S., additional, Baroch, D., additional, Bastelberger, S. T., additional, Chaturvedi, P., additional, Cifuentes, C., additional, Dreizler, S., additional, Jeffers, S. V., additional, Kopparapu, R., additional, Lafarga, M., additional, López-González, M. J., additional, Martín-Ruiz, S., additional, Montes, D., additional, Morales, J. C., additional, Pallé, E., additional, Pavlov, A., additional, Pedraz, S., additional, Perdelwitz, V., additional, Pérez-Torres, M., additional, Perger, M., additional, Reffert, S., additional, Rodríguez López, C., additional, Schlecker, M., additional, Schöfer, P., additional, Schweitzer, A., additional, Shan, Y., additional, Shields, A., additional, Stock, S., additional, Wolf, E., additional, Zapatero Osorio, M. R., additional, and Zechmeister, M., additional

Published
2023
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16. The CARMENES search for exoplanets around M dwarfs

Author

Ribas, I., primary, Reiners, A., additional, Zechmeister, M., additional, Caballero, J. A., additional, Morales, J. C., additional, Sabotta, S., additional, Baroch, D., additional, Amado, P. J., additional, Quirrenbach, A., additional, Abril, M., additional, Aceituno, J., additional, Anglada-Escudé, G., additional, Azzaro, M., additional, Barrado, D., additional, Béjar, V. J. S., additional, Benítez de Haro, D., additional, Bergond, G., additional, Bluhm, P., additional, Calvo Ortega, R., additional, Cardona Guillén, C., additional, Chaturvedi, P., additional, Cifuentes, C., additional, Colomé, J., additional, Cont, D., additional, Cortés-Contreras, M., additional, Czesla, S., additional, Díez-Alonso, E., additional, Dreizler, S., additional, Duque-Arribas, C., additional, Espinoza, N., additional, Fernández, M., additional, Fuhrmeister, B., additional, Galadí-Enríquez, D., additional, García-López, A., additional, González-Álvarez, E., additional, González Hernández, J. I., additional, Guenther, E. W., additional, de Guindos, E., additional, Hatzes, A. P., additional, Henning, Th., additional, Herrero, E., additional, Hintz, D., additional, Huelmo, Á. L., additional, Jeffers, S. V., additional, Johnson, E. N., additional, de Juan, E., additional, Kaminski, A., additional, Kemmer, J., additional, Khaimova, J., additional, Khalafinejad, S., additional, Kossakowski, D., additional, Kürster, M., additional, Labarga, F., additional, Lafarga, M., additional, Lalitha, S., additional, Lampón, M., additional, Lillo-Box, J., additional, Lodieu, N., additional, López González, M. J., additional, López-Puertas, M., additional, Luque, R., additional, Magán, H., additional, Mancini, L., additional, Marfil, E., additional, Martín, E. L., additional, Martín-Ruiz, S., additional, Molaverdikhani, K., additional, Montes, D., additional, Nagel, E., additional, Nortmann, L., additional, Nowak, G., additional, Pallé, E., additional, Passegger, V. M., additional, Pavlov, A., additional, Pedraz, S., additional, Perdelwitz, V., additional, Perger, M., additional, Ramón-Ballesta, A., additional, Reffert, S., additional, Revilla, D., additional, Rodríguez, E., additional, Rodríguez-López, C., additional, Sadegi, S., additional, Sánchez Carrasco, M. Á., additional, Sánchez-López, A., additional, Sanz-Forcada, J., additional, Schäfer, S., additional, Schlecker, M., additional, Schmitt, J. H. M. M., additional, Schöfer, P., additional, Schweitzer, A., additional, Seifert, W., additional, Shan, Y., additional, Skrzypinski, S. L., additional, Solano, E., additional, Stahl, O., additional, Stangret, M., additional, Stock, S., additional, Stürmer, J., additional, Tabernero, H. M., additional, Tal-Or, L., additional, Trifonov, T., additional, Vanaverbeke, S., additional, Yan, F., additional, and Zapatero Osorio, M. R., additional

Published
2023
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17. The CARMENES search for exoplanets around M dwarfs

Author

Ribas, I, Reiners, A, Zechmeister, M, Caballero, Ja, Morales, Jc, Sabotta, S, Baroch, D, Amado, Pj, Quirrenbach, A, Abril, M, Aceituno, J, Anglada-Escudé, G, Azzaro, M, Barrado, D, Béjar, Vjs, Benítez de Haro, D, Bergond, G, Bluhm, P, Calvo Ortega, R, Cardona Guillén, C, Chaturvedi, P, Cifuentes, C, Colomé, J, Cont, D, Cortés-Contreras, M, Czesla, S, Díez-Alonso, E, Dreizler, S, Duque-Arribas, C, Espinoza, N, Fernández, M, Fuhrmeister, B, Galadí-Enríquez, D, García-López, A, González-Álvarez, E, González Hernández, Ji, Guenther, Ew, de Guindos, E, Hatzes, Ap, Henning, T, Herrero, E, Hintz, D, Huelmo, Al, Jeffers, Sv, Johnson, En, de Juan, E, Kaminski, A, Kemmer, J, Khaimova, J, Khalafinejad, S, Kossakowski, D, Kürster, M, Labarga, F, Lafarga, M, Lalitha, S, Lampón, M, Lillo-Box, J, Lodieu, N, López González, Mj, López-Puertas, M, Luque, R, Magán, H, Mancini, L, Marfil, E, Martín, El, Martín-Ruiz, S, Molaverdikhani, K, Montes, D, Nagel, E, Nortmann, L, Nowak, G, Pallé, E, Passegger, Vm, Pavlov, A, Pedraz, S, Perdelwitz, V, Perger, M, Ramón-Ballesta, A, Reffert, S, Revilla, D, Rodríguez, E, Rodríguez-López, C, Sadegi, S, Sánchez Carrasco, Ma, Sánchez-López, A, Sanz-Forcada, J, Schäfer, S, Schlecker, M, Schmitt, Jhmm, Schöfer, P, Schweitzer, A, Seifert, W, Shan, Y, Skrzypinski, Sl, Solano, E, Stahl, O, Stangret, M, Stock, S, Stürmer, J, Tabernero, Hm, Tal-Or, L, Trifonov, T, Vanaverbeke, S, Yan, F, and Zapatero Osorio, Mr

Subjects
Astrophysics - Solar and Stellar Astrophysics, solar neighborhood, Settore FIS/05, stars: late-type, techniques: spectroscopic, astronomical databases: miscellaneous, planetary systems, Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Published
2023

18. The CARMENES search for exoplanets around M dwarfs

Author

Kossakowski, D., primary, Kürster, M., additional, Henning, Th, additional, Trifonov, T., additional, Caballero, J. A., additional, Lafarga, M., additional, Bauer, F. F, additional, Stock, S., additional, Kemmer, J., additional, Jeffers, S. V., additional, Amado, P. J., additional, Pérez-Torres, M., additional, Béjar, V. J. S., additional, Cortés-Contreras, M., additional, Ribas, I., additional, Reiners, A., additional, Quirrenbach, A., additional, Aceituno, J., additional, Baroch, D., additional, Cifuentes, C., additional, Dreizler, S., additional, Hatzes, A., additional, Kaminski, A., additional, Montes, D., additional, Morales, J. C., additional, Pavlov, A., additional, Pena, L., additional, Perdelwitz, V., additional, Reffert, S., additional, Revilla, D., additional, Lopez, C. Rodriguez, additional, Rosich, A., additional, Sadegi, S., additional, Sanz-Forcada, J., additional, Schöfer, P., additional, Schweitzer, A., additional, and Zechmeister, M., additional

Published
2022
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19. The HD 260655 system: Two rocky worlds transiting a bright M dwarf at 10 pc

Author

Luque, R., primary, Fulton, B. J., additional, Kunimoto, M., additional, Amado, P. J., additional, Gorrini, P., additional, Dreizler, S., additional, Hellier, C., additional, Henry, G. W., additional, Molaverdikhani, K., additional, Morello, G., additional, Peña-Moñino, L., additional, Pérez-Torres, M., additional, Pozuelos, F. J., additional, Shan, Y., additional, Anglada-Escudé, G., additional, Béjar, V. J. S., additional, Bergond, G., additional, Boyle, A. W., additional, Caballero, J. A., additional, Charbonneau, D., additional, Ciardi, D. R., additional, Dufoer, S., additional, Espinoza, N., additional, Everett, M., additional, Fischer, D., additional, Hatzes, A. P., additional, Henning, Th., additional, Hesse, K., additional, Howard, A. W., additional, Howell, S. B., additional, Isaacson, H., additional, Jeffers, S. V., additional, Jenkins, J. M., additional, Kane, S. R., additional, Kemmer, J., additional, Khalafinejad, S., additional, Kidwell, R. C., additional, Kossakowski, D., additional, Latham, D. W., additional, Lillo-Box, J., additional, Lissauer, J. J., additional, Montes, D., additional, Orell-Miquel, J., additional, Pallé, E., additional, Pollacco, D., additional, Quirrenbach, A., additional, Reffert, S., additional, Reiners, A., additional, Ribas, I., additional, Ricker, G. R., additional, Rogers, L. A., additional, Sanz-Forcada, J., additional, Schlecker, M., additional, Schweitzer, A., additional, Seager, S., additional, Shporer, A., additional, Stassun, K. G., additional, Stock, S., additional, Tal-Or, L., additional, Ting, E. B., additional, Trifonov, T., additional, Vanaverbeke, S., additional, Vanderspek, R., additional, Villaseñor, J., additional, Winn, J. N., additional, Winters, J. G., additional, and Zapatero Osorio, M. R., additional

Published
2022
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20. The CARMENES search for exoplanets around M dwarfs: Stable radial-velocity variations at the rotation period of AD Leonis: A test case study of current limitations to treating stellar activity

Author

Ministerio de Ciencia e Innovación (España), European Commission, Kossakowski, D., Kürster, M., Henning, Thomas, Trifonov, T., Caballero, J. A., Lafarga, M., Bauer, Florian Franz, Stock, S., Kemmer, J., Jeffers, Sandra V., Amado, Pedro J., Pérez-Torres, Miguel A., Béjar, Victor J. S., Cortés-Contreras, M., Ribas, Ignasi, Reiners, Ansgar, Quirrenbach, Andreas, Aceituno, Jesús, Baroch, David, Cifuentes, C., Dreizler, S., Hatzes, Artie P., Kaminski, A., Montes, D., Morales, Juan Carlos, Pavlov, A., Peña-Moñino, Luis, Perdelwitz, Volker, Reffert, S., Revilla, D., Rodríguez López, C., Rosich, A., Sadegi, S., Sanz-Forcada, J., Schöfer, P., Schweitzer, Andreas, Zechmeister, Mathias, Ministerio de Ciencia e Innovación (España), European Commission, Kossakowski, D., Kürster, M., Henning, Thomas, Trifonov, T., Caballero, J. A., Lafarga, M., Bauer, Florian Franz, Stock, S., Kemmer, J., Jeffers, Sandra V., Amado, Pedro J., Pérez-Torres, Miguel A., Béjar, Victor J. S., Cortés-Contreras, M., Ribas, Ignasi, Reiners, Ansgar, Quirrenbach, Andreas, Aceituno, Jesús, Baroch, David, Cifuentes, C., Dreizler, S., Hatzes, Artie P., Kaminski, A., Montes, D., Morales, Juan Carlos, Pavlov, A., Peña-Moñino, Luis, Perdelwitz, Volker, Reffert, S., Revilla, D., Rodríguez López, C., Rosich, A., Sadegi, S., Sanz-Forcada, J., Schöfer, P., Schweitzer, Andreas, and Zechmeister, Mathias

Abstract

Context. A challenge with radial-velocity (RV) data is disentangling the origin of signals either due to a planetary companion or to stellar activity. In fact, the existence of a planetary companion has been proposed, as well as contested, around the relatively bright, nearby M3.0 V star AD Leo at the same period as the stellar rotation of 2.23 days. Aims. We further investigate the nature of this signal. We introduce new CARMENES optical and near-IR RV data and an analysis in combination with archival data taken by HIRES and HARPS, along with more recent data from HARPS-N, GIANO-B, and HPF. Additionally, we address the confusion concerning the binarity of AD Leo. Methods. We consider possible correlations between the RVs and various stellar activity indicators accessible with CARMENES. We additionally applied models within a Bayesian framework to determine whether a Keplerian model, a red-noise quasi-periodic model using a Gaussian process, or a mixed model would explain the observed data best. We also exclusively focus on spectral lines potentially associated with stellar activity. Results. The CARMENES RV data agree with the previously reported periodicity of 2.23 days, correlate with some activity indicators, and exhibit chromaticity. However, when considering the entire RV data set, we find that a mixed model composed of a stable and a variable component performs best. Moreover, when recomputing the RVs using only spectral lines insensitive to activity, there appears to be some residual power at the period of interest. We therefore conclude that it is not possible to determinedly prove that there is no planet orbiting in synchronization with the stellar rotation given our data, current tools, machinery, and knowledge of how stellar activity affects RVs. We do rule out planets more massive than 27 M⊕ (=0.084 MJup). Likewise, we exclude any binary companion around AD Leo with M sin i greater than 3–6 MJup on orbital periods <14 yr. © D. Kossakowski et al. 2022.

Published
2022

21. A multi-planetary system orbiting the early-M dwarf TOI-1238

Author

European Commission, Ministerio de Ciencia e Innovación (España), National Aeronautics and Space Administration (US), González-Álvarez, E., Zapatero Osorio, María Rosa, Sanz-Forcada, J., Caballero, J. A., Reffert, S., Béjar, Victor J. S., Hatzes, Artie P., Herrero, E., Jeffers, Sandra V., Kemmer, J., López González, Maria J., Luque, R., Molaverdikhani, K., Morello, G., Nagel, Evangelos, Quirrenbach, Andreas, Rodríguez Martínez, Eloy, Rodríguez-López, Cristina, Schlecker, M., Schweitzer, Andreas, Stock, S., Passegger, V.M., Trifonov, T., Amado, Pedro J., Baker, D., Boyd, P. T., Cadieux, Charles, Charbonneau, David, Collins, Karen A., Doyon, R., Dreizler, S., Espinoza, Néstor, Fűrész, G., Furlan, E., Hesse, K., Howell, S.B., Jenkins, Jon M., Kidwell, R. C., Latham, David W., McLeod, K. K., Montes, D., Morales, Juan Carlos, O'Dwyer, T., Pallé, Enric, Pedraz, S., Reiners, Ansgar, Ribas, Ignasi, Quinn, S. N., Schnaible, C., Seager, S., Skinner, B., Smith, J. C., Schwarz, R. P., Shporer, A., Vanderspek, R., Winn, J. N., European Commission, Ministerio de Ciencia e Innovación (España), National Aeronautics and Space Administration (US), González-Álvarez, E., Zapatero Osorio, María Rosa, Sanz-Forcada, J., Caballero, J. A., Reffert, S., Béjar, Victor J. S., Hatzes, Artie P., Herrero, E., Jeffers, Sandra V., Kemmer, J., López González, Maria J., Luque, R., Molaverdikhani, K., Morello, G., Nagel, Evangelos, Quirrenbach, Andreas, Rodríguez Martínez, Eloy, Rodríguez-López, Cristina, Schlecker, M., Schweitzer, Andreas, Stock, S., Passegger, V.M., Trifonov, T., Amado, Pedro J., Baker, D., Boyd, P. T., Cadieux, Charles, Charbonneau, David, Collins, Karen A., Doyon, R., Dreizler, S., Espinoza, Néstor, Fűrész, G., Furlan, E., Hesse, K., Howell, S.B., Jenkins, Jon M., Kidwell, R. C., Latham, David W., McLeod, K. K., Montes, D., Morales, Juan Carlos, O'Dwyer, T., Pallé, Enric, Pedraz, S., Reiners, Ansgar, Ribas, Ignasi, Quinn, S. N., Schnaible, C., Seager, S., Skinner, B., Smith, J. C., Schwarz, R. P., Shporer, A., Vanderspek, R., and Winn, J. N.

Abstract

Context. The number of super-Earth and Earth-mass planet discoveries has increased significantly in the last two decades thanks to the Doppler radial velocity and planetary transit observing techniques. Either technique can detect planet candidates on its own, but the power of a combined photometric and spectroscopic analysis is unique for an insightful characterization of the planets, which in turn has repercussions for our understanding of the architecture of planetary systems and, therefore, their formation and evolution. Aims. Two transiting planet candidates with super-Earth radii around the nearby (d = 70.64 ± 0.06 pc) K7–M0 dwarf star TOI-1238 were announced by NASA’s Transiting Exoplanet Survey Satellite (TESS), which observed the field of TOI-1238 in four different sectors. We aim to validate their planetary nature using precise radial velocities taken with the CARMENES spectrograph. Methods. We obtained 55 CARMENES radial velocity measurements that span the 11 months between 9 May 2020 and 5 April 2021. For a better characterization of the parent star’s activity, we also collected contemporaneous optical photometric observations at the Joan Oró and Sierra Nevada observatories and retrieved archival photometry from the literature. We performed a combined TESS+CARMENES photometric and spectroscopic analysis by including Gaussian processes and Keplerian orbits to account for the stellar activity and planetary signals simultaneously. Results. We estimate that TOI-1238 has a rotation period of 40 ± 5 d based on photometric and spectroscopic data. The combined analysis confirms the discovery of two transiting planets, TOI-1238 b and c, with orbital periods of 0.764597−0.000011+0.000013 d and 3.294736−0.000036+0.000034 d, masses of 3.76−1.07+1.15 M⊕ and 8.32−1.88+1.90 M⊕, and radii of 1.21−0.10+0.11 R⊕ and 2.11−0.14+0.14 R⊕. They orbit their parent star at semimajor axes of 0.0137 ± 0.0004 au and 0.036 ± 0.001 au, respectively.The two planets are placed on opposi

Published
2022

22. Discovery and mass measurement of the hot, transiting, Earth-sized planet, GJ 3929 b

Author

Kemmer, J., primary, Dreizler, S., additional, Kossakowski, D., additional, Stock, S., additional, Quirrenbach, A., additional, Caballero, J. A., additional, Amado, P. J., additional, Collins, K. A., additional, Espinoza, N., additional, Herrero, E., additional, Jenkins, J. M., additional, Latham, D. W., additional, Lillo-Box, J., additional, Narita, N., additional, Pallé, E., additional, Reiners, A., additional, Ribas, I., additional, Ricker, G., additional, Rodríguez, E., additional, Seager, S., additional, Vanderspek, R., additional, Wells, R., additional, Winn, J., additional, Aceituno, F. J., additional, Béjar, V. J. S., additional, Barclay, T., additional, Bluhm, P., additional, Chaturvedi, P., additional, Cifuentes, C., additional, Collins, K. I., additional, Cortés-Contreras, M., additional, Demory, B.-O., additional, Fausnaugh, M. M., additional, Fukui, A., additional, Gómez Maqueo Chew, Y., additional, Galadí-Enríquez, D., additional, Gan, T., additional, Gillon, M., additional, Golovin, A., additional, Hatzes, A. P., additional, Henning, Th., additional, Huang, C., additional, Jeffers, S. V., additional, Kaminski, A., additional, Kunimoto, M., additional, Kürster, M., additional, López-González, M. J., additional, Lafarga, M., additional, Luque, R., additional, McCormac, J., additional, Molaverdikhani, K., additional, Montes, D., additional, Morales, J. C., additional, Passegger, V. M., additional, Reffert, S., additional, Sabin, L., additional, Schöfer, P., additional, Schanche, N., additional, Schlecker, M., additional, Schroffenegger, U., additional, Schwarz, R. P., additional, Schweitzer, A., additional, Sota, A., additional, Tenenbaum, P., additional, Trifonov, T., additional, Vanaverbeke, S., additional, and Zechmeister, M., additional

Published
2022
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23. A multi-planetary system orbiting the early-M dwarf TOI-1238

Author

González-Álvarez, E., primary, Zapatero Osorio, M. R., additional, Sanz-Forcada, J., additional, Caballero, J. A., additional, Reffert, S., additional, Béjar, V. J. S., additional, Hatzes, A. P., additional, Herrero, E., additional, Jeffers, S. V., additional, Kemmer, J., additional, López-González, M. J., additional, Luque, R., additional, Molaverdikhani, K., additional, Morello, G., additional, Nagel, E., additional, Quirrenbach, A., additional, Rodríguez, E., additional, Rodríguez-López, C., additional, Schlecker, M., additional, Schweitzer, A., additional, Stock, S., additional, Passegger, V. M., additional, Trifonov, T., additional, Amado, P. J., additional, Baker, D., additional, Boyd, P. T., additional, Cadieux, C., additional, Charbonneau, D., additional, Collins, K. A., additional, Doyon, R., additional, Dreizler, S., additional, Espinoza, N., additional, Fűrész, G., additional, Furlan, E., additional, Hesse, K., additional, Howell, S. B., additional, Jenkins, J. M., additional, Kidwell, R. C., additional, Latham, D. W., additional, McLeod, K. K., additional, Montes, D., additional, Morales, J. C., additional, O’Dwyer, T., additional, Pallé, E., additional, Pedraz, S., additional, Reiners, A., additional, Ribas, I., additional, Quinn, S. N., additional, Schnaible, C., additional, Seager, S., additional, Skinner, B., additional, Smith, J. C., additional, Schwarz, R. P., additional, Shporer, A., additional, Vanderspek, R., additional, and Winn, J. N., additional

Published
2022
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24. TOI-1201 b: A mini-Neptune transiting a bright and moderately young M dwarf

Author

Kossakowski, D., primary, Kemmer, J., additional, Bluhm, P., additional, Stock, S., additional, Caballero, J. A., additional, Béjar, V. J. S., additional, Guillén, C. Cardona, additional, Lodieu, N., additional, Collins, K. A., additional, Oshagh, M., additional, Schlecker, M., additional, Espinoza, N., additional, Pallé, E., additional, Henning, Th., additional, Kreidberg, L., additional, Kürster, M., additional, Amado, P. J., additional, Anderson, D. R., additional, Morales, J. C., additional, Cartwright, S., additional, Charbonneau, D., additional, Chaturvedi, P., additional, Cifuentes, C., additional, Conti, D. M., additional, Cortés-Contreras, M., additional, Dreizler, S., additional, Galadí-Enríquez, D., additional, Guerra, P., additional, Hart, R., additional, Hellier, C., additional, Henze, C., additional, Herrero, E., additional, Jeffers, S. V., additional, Jenkins, J. M., additional, Jensen, E. L. N., additional, Kaminski, A., additional, Kielkopf, J. F., additional, Kunimoto, M., additional, Lafarga, M., additional, Latham, D. W., additional, Lillo-Box, J., additional, Luque, R., additional, Molaverdikhani, K., additional, Montes, D., additional, Morello, G., additional, Morgan, E. H., additional, Nowak, G., additional, Pavlov, A., additional, Perger, M., additional, Quintana, E. V., additional, Quirrenbach, A., additional, Reffert, S., additional, Reiners, A., additional, Ricker, G., additional, Ribas, I., additional, López, C. Rodríguez, additional, Osorio, M. R. Zapatero, additional, Seager, S., additional, Schöfer, P., additional, Schweitzer, A., additional, Trifonov, T., additional, Vanaverbeke, S., additional, Vanderspek, R., additional, West, R., additional, Winn, J., additional, and Zechmeister, M., additional

Published
2021
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25. FoxO3 Modulates Circadian Rhythms in Neural Stem Cells.

Author

Draijer S, Timmerman R, Pannekeet J, van Harten A, Farshadi EA, Kemmer J, van Gilst D, Chaves I, and Hoekman MFM

Subjects
Animals, Mice, Cell Cycle, Cell Division, Circadian Clocks genetics, Circadian Rhythm genetics, Neural Stem Cells, Forkhead Box Protein O3 genetics, Forkhead Box Protein O3 physiology
Abstract

Both FoxO transcription factors and the circadian clock act on the interface of metabolism and cell cycle regulation and are important regulators of cellular stress and stem cell homeostasis. Importantly, FoxO3 preserves the adult neural stem cell population by regulating cell cycle and cellular metabolism and has been shown to regulate circadian rhythms in the liver. However, whether FoxO3 is a regulator of circadian rhythms in neural stem cells remains unknown. Here, we show that loss of FoxO3 disrupts circadian rhythmicity in cultures of neural stem cells, an effect that is mediated via regulation of Clock transcriptional levels. Using Rev-Erbα-VNP as a reporter, we then demonstrate that loss of FoxO3 does not disrupt circadian rhythmicity at the single cell level. A meta-analysis of published data revealed dynamic co-occupancy of multiple circadian clock components within FoxO3 regulatory regions, indicating that FoxO3 is a Clock-controlled gene. Finally, we examined proliferation in the hippocampus of FoxO3-deficient mice and found that loss of FoxO3 delayed the circadian phase of hippocampal proliferation, indicating that FoxO3 regulates correct timing of NSC proliferation. Taken together, our data suggest that FoxO3 is an integral part of circadian regulation of neural stem cell homeostasis.

Published
2023
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26. Implementation of Telehealth for Psychiatric Care in VA Emergency Departments and Urgent Care Clinics.

Author

Ward MJ, Shuster JL , Jr, Mohr NM, Kaboli PJ, Mixon AS, Kemmer J, Campbell C, and McNaughton CD

Subjects
Ambulatory Care Facilities, Emergency Service, Hospital, Humans, Pandemics, COVID-19 epidemiology, Telemedicine
Abstract

Objective: To conduct a mixed-methods evaluation of an emergency telehealth intervention in unscheduled settings (emergency department [ED] and urgent care clinic [UCC]) within the Veterans Health Administration (VHA). Materials and Methods: We used the Reach, Effectiveness, Adoption, Implementation, Maintenance (RE-AIM) framework to conduct a mixed-methods evaluation of a novel telehealth program implemented in the VHA (Hospital System) in March 2020. We compared the 3 months preimplementation (December 1, 2019 through February 29, 2020) with the 3 months postimplementation (April 1, 2020 through June 30, 2020), then followed sustainability through January 31, 2021. Qualitative data were obtained from surveys and semistructured interviews of staff and providers and analyzed with thematic analysis. Results: Patient demographics and dispositions were similar pre- and postimplementation. The telemental health intervention was used in 319 (83%) unscheduled mental health consultations in the postimplementation phase. After implementation, we did not detect adverse trends in length of stay, 7-day revisits, or 30-day mortality. Use remained high with 82% ( n  = 1,010) of all unscheduled mental health consultations performed by telemental health in the sustainability phase. Staff and clinician interviews identified the following themes in the use of telemental health: (1) enhanced efficiency without compromising quality and safety, (2) initial apprehension, (3) the COVID-19 pandemic, and (4) sustainability after resolution of the COVID-19 pandemic. Conclusions: This mixed-methods evaluation of unscheduled telemental health implementation found that its use was feasible, did not impact the safety and efficacy of mental health consultations, and was highly acceptable and sustainable in unscheduled settings.

Published
2022
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