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2. Constraining the Nature of the PDS 70 Protoplanets with VLTI/GRAVITY

Author

Wang, J. J., Vigan, A., Lacour, S., Nowak, M., Stolker, T., De Rosa, R. J., Ginzburg, S., Gao, P., Abuter, R., Amorim, A., Asensio-Torres, R., Baubck, M., Benisty, M., Berger, J. P., Beust, H., Beuzit, J. -L., Blunt, S., Boccaletti, A., Bohn, A., Bonnefoy, M., Bonnet, H., Brandner, W., Cantalloube, F., Caselli, P., Charnay, B., Chauvin, G., Choquet, E., Christiaens, V., Clénet, Y., Foresto, V. Coudé du, Cridland, A., de Zeeuw, P. T., Dembet, R., Dexter, J., Drescher, A., Duvert, G., Eckart, A., Eisenhauer, F., Facchini, S., Gao, F., Garcia, P., Lopez, R. Garcia, Gardner, T., Gendron, E., Genzel, R., Gillessen, S., Girard, J., Haubois, X., Heißel, G., Henning, T., Hinkley, S., Hippler, S., Horrobin, M., Houllé, M., Hubert, Z., Jiménez-Rosales, A., Jocou, L., Kammerer, J., Keppler, M., Kervella, P., Meyer, M., Kreidberg, L., Lagrange, A. -M., Lapeyrère, V., Bouquin, J. -B. Le, Léna, P., Lutz, D., Maire, A. -L., Ménard, F., Mérand, A., Mollière, P., Monnier, J. D., Mouillet, D., Müller, A., Nasedkin, E., Ott, T., Otten, G. P. P. L., Paladini, C., Paumard, T., Perraut, K., Perrin, G., Pfuhl, O., Pueyo, L., Rameau, J., Rodet, L., Rodríguez-Coira, G., Rousset, G., Scheithauer, S., Shangguan, J., Shimizu, T., Stadler, J., Straub, O., Straubmeier, C., Sturm, E., Tacconi, L. J., van Dishoeck, E. F., Vincent, F., von Fellenberg, S. D., Ward-Duong, K., Widmann, F., Wieprecht, E., Wiezorrek, E., Woillez, J., and Collaboration, The GRAVITY

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

We present K-band interferometric observations of the PDS 70 protoplanets along with their host star using VLTI/GRAVITY. We obtained K-band spectra and 100 $\mu$as precision astrometry of both PDS 70 b and c in two epochs, as well as spatially resolving the hot inner disk around the star. Rejecting unstable orbits, we found a nonzero eccentricity for PDS 70 b of $0.17 \pm 0.06$, a near-circular orbit for PDS 70 c, and an orbital configuration that is consistent with the planets migrating into a 2:1 mean motion resonance. Enforcing dynamical stability, we obtained a 95% upper limit on the mass of PDS 70 b of 10 $M_\textrm{Jup}$, while the mass of PDS 70 c was unconstrained. The GRAVITY K-band spectra rules out pure blackbody models for the photospheres of both planets. Instead, the models with the most support from the data are planetary atmospheres that are dusty, but the nature of the dust is unclear. Any circumplanetary dust around these planets is not well constrained by the planets' 1-5 $\mu$m spectral energy distributions (SEDs) and requires longer wavelength data to probe with SED analysis. However with VLTI/GRAVITY, we made the first observations of a circumplanetary environment with sub-au spatial resolution, placing an upper limit of 0.3~au on the size of a bright disk around PDS 70 b., Comment: 30 pages, 9 figures, Accepted for publication in AJ

Published
2021
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3. Supernova PTF 12glz: A Possible Shock Breakout Driven through an Aspherical Wind

Author

Soumagnac, MT, Ofek, EO, Gal-Yam, A, Waxman, E, Ginzburg, S, Strotjohann, NL, Schulze, S, Barlow, TA, Behar, E, Chelouche, D, Fremling, C, Ganot, N, Gezari, S, Kasliwal, MM, Kaspi, S, Kulkarni, SR, Laher, RR, Maoz, D, Martin, CD, Nakar, E, Neill, JD, Nugent, PE, Poznanski, D, and Yaron, O

Subjects
circumstellar matter, supernovae: general, supernovae: individual, ultraviolet: stars, astro-ph.HE, astro-ph.SR, Astronomical And Space Sciences, Organic Chemistry, Physical Chemistry, Astronomy & Astrophysics, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Physical Chemistry (incl. Structural)
Abstract

We present visible-light and ultraviolet (UV) observations of the supernova PTF 12glz. The SN was discovered and monitored in the near-UV and R bands as part of a joint GALEX and Palomar Transient Factory campaign. It is among the most energetic SNe IIn observed to date (≈10 51 erg). If the radiated energy mainly came from the thermalization of the shock kinetic energy, we show that PTF 12glz was surrounded by ∼1 M of circumstellar material (CSM) prior to its explosive death. PTF 12glz shows a puzzling peculiarity: at early times, while the freely expanding ejecta are presumably masked by the optically thick CSM, the radius of the blackbody that best fits the observations grows at ≈7000 km s -1 . Such a velocity is characteristic of fast moving ejecta rather than optically thick CSM. This phase of radial expansion takes place before any spectroscopic signature of expanding ejecta appears in the spectrum and while both the spectroscopic data and the bolometric luminosity seem to indicate that the CSM is optically thick. We propose a geometrical solution to this puzzle, involving an aspherical structure of the CSM around PTF 12glz. By modeling radiative diffusion through a slab of CSM, we show that an aspherical geometry of the CSM can result in a growing effective radius. This simple model also allows us to recover the decreasing blackbody temperature of PTF 12glz. SLAB-Diffusion, the code we wrote to model the radiative diffusion of photons through a slab of CSM and evaluate the observed radius and temperature, is made available online.

Published
2019

6. Avalanches in directed complex networks of neurons connected by stochastic synapses

Author

Ginzburg, S. L. and Pustovoit, M. A.

Subjects
Condensed Matter - Disordered Systems and Neural Networks
Abstract

Directed complex network of two-state model neurons linked by synapses which can be blocked or activated stochastically in time undergoes phase transition between the quiescent phase with zero activity and the active one with persistent activity. Avalanches of activity appear in the quiescent phase after occasional excitation of randomly chosen neuron. Size and duration distributions of long avalanches which we observe near phase transition point are exponential. Only a small fraction of all neurons are active at any moment of a long avalanche., Comment: 4 figures, submitted to EPL

Published
2009

7. Magnetic flux dynamics in critical state of one-dimensional discrete superconductor

Author

Ginzburg, S. L., Nakin, A. V., and Savitskaya, N. E.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Disordered Systems and Neural Networks
Abstract

We give a theoretical description of avalanche-like dynamics of magnetic flux in the critical state of "hard" type-II superconductors using a model of a one-dimensional multijunction SQUID that well reproduces the main magnetic properties of these objects. We show that the system under consideration demonstrates the self-organized criticality. The avalanches of vortices manifest themselves as jumps of the total magnetic flux in the sample. The sizes of these jumps have a power-law distribution. Our results are in qualitative agreement with experiments., Comment: 7 pages, 5 figures

Published
2005
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15. Constraining the nature of the PDS 70 protoplanets with VLTI/GRAVITY

Author

Wang, JJ, Vigan, A, Lacour, S, Nowak, M, Stolker, T, De Rosa, RJ, Ginzburg, S, Gao, P, Abuter, R, Amorim, A, Asensio-Torres, R, Bauböck, M, Benisty, M, Berger, JP, Beust, H, Beuzit, JL, Blunt, S, Boccaletti, A, Bohn, A, Bonnefoy, M, Bonnet, H, Brandner, W, Cantalloube, F, Caselli, P, Charnay, B, Chauvin, G, Choquet, E, Christiaens, V, Clénet, Y, Coudé Du Foresto, V, Cridland, A, De Zeeuw, PT, Dembet, R, Dexter, J, Drescher, A, Duvert, G, Eckart, A, Eisenhauer, F, Facchini, S, Gao, F, Garcia, P, Garcia Lopez, R, Gardner, T, Gendron, E, Genzel, R, Gillessen, S, Girard, J, Haubois, X, Heißel, G, Henning, T, Hinkley, S, Hippler, S, Horrobin, M, Houllé, M, Hubert, Z, Jiménez-Rosales, A, Jocou, L, Kammerer, J, Keppler, M, Kervella, P, Meyer, M, Kreidberg, L, Lagrange, AM, Lapeyrère, V, Le Bouquin, JB, Léna, P, Lutz, D, Maire, AL, Ménard, F, Mérand, A, Mollière, P, Monnier, JD, Mouillet, D, Müller, A, Nasedkin, E, Ott, T, Otten, GPPL, Paladini, C, Paumard, T, Perraut, K, Perrin, G, Pfuhl, O, Pueyo, L, Rameau, J, Rodet, L, Rodríguez-Coira, G, Rousset, G, Scheithauer, S, Shangguan, J, Shimizu, T, Stadler, J, Straub, O, Straubmeier, C, Sturm, E, Tacconi, LJ, Van Dishoeck, EF, Vincent, F, Von Fellenberg, SD, Ward-Duong, K, Widmann, F, Wang, JJ [0000-0003-0774-6502], Vigan, A [0000-0002-5902-7828], Lacour, S [0000-0002-6948-0263], Stolker, T [0000-0002-5823-3072], De Rosa, RJ [0000-0002-4918-0247], Gao, P [0000-0002-8518-9601], Asensio-Torres, R [0000-0003-2990-0726], Benisty, M [0000-0002-7695-7605], Beuzit, JL [0000-0002-7391-479X], Blunt, S [0000-0002-3199-2888], Bohn, A [0000-0003-1401-9952], Bonnefoy, M [0000-0001-5579-5339], Brandner, W [0000-0003-1939-6351], Caselli, P [0000-0003-1481-7911], Charnay, B [0000-0003-0977-6545], Choquet, E [0000-0002-9173-0740], Christiaens, V [0000-0002-0101-8814], Clénet, Y [0000-0002-8382-2020], De Zeeuw, PT [0000-0003-4175-3474], Dexter, J [0000-0003-3903-0373], Eckart, A [0000-0001-6049-3132], Facchini, S [0000-0003-4689-2684], Gao, F [0000-0002-2581-9114], Garcia Lopez, R [0000-0002-2144-0991], Gardner, T [0000-0002-3003-3183], Genzel, R [0000-0002-2767-9653], Gillessen, S [0000-0002-5708-0481], Girard, J [0000-0001-8627-0404], Henning, T [0000-0002-1493-300X], Hinkley, S [0000-0001-8074-2562], Hippler, S [0000-0002-3912-6108], Horrobin, M [0000-0001-5451-7847], Kervella, P [0000-0003-0626-1749], Meyer, M [0000-0003-1227-3084], Kreidberg, L [0000-0003-0514-1147], Le Bouquin, JB [0000-0002-0493-4674], Lutz, D [0000-0003-0291-9582], Maire, AL [0000-0002-2591-4138], Mérand, A [0000-0002-1637-7393], Monnier, JD [0000-0002-3380-3307], Ott, T [0000-0003-1572-0396], Paumard, T [0000-0003-0655-0452], Perrin, G [0000-0003-0680-0167], Rameau, J [0000-0003-0029-0258], Rodríguez-Coira, G [0000-0002-4177-6433], Shangguan, J [0000-0002-4569-9009], Shimizu, T [0000-0002-2125-4670], Straub, O [0000-0001-5755-0677], Straubmeier, C [0000-0002-0671-9302], Sturm, E [0000-0002-0018-3666], Tacconi, LJ [0000-0002-1485-9401], Van Dishoeck, EF [0000-0001-7591-1907], Vincent, F [0000-0002-3855-0708], Von Fellenberg, SD [0000-0002-9156-2249], Ward-Duong, K [0000-0002-4479-8291], and Apollo - University of Cambridge Repository

Subjects
Orbit determination, Exoplanet formation, Long baseline interferometry, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Exoplanet atmospheres
Abstract

We present K-band interferometric observations of the PDS 70 protoplanets along with their host star using VLTI/GRAVITY. We obtained K-band spectra and 100 $\mu$as precision astrometry of both PDS 70 b and c in two epochs, as well as spatially resolving the hot inner disk around the star. Rejecting unstable orbits, we found a nonzero eccentricity for PDS 70 b of $0.17 \pm 0.06$, a near-circular orbit for PDS 70 c, and an orbital configuration that is consistent with the planets migrating into a 2:1 mean motion resonance. Enforcing dynamical stability, we obtained a 95% upper limit on the mass of PDS 70 b of 10 $M_\textrm{Jup}$, while the mass of PDS 70 c was unconstrained. The GRAVITY K-band spectra rules out pure blackbody models for the photospheres of both planets. Instead, the models with the most support from the data are planetary atmospheres that are dusty, but the nature of the dust is unclear. Any circumplanetary dust around these planets is not well constrained by the planets' 1-5 $\mu$m spectral energy distributions (SEDs) and requires longer wavelength data to probe with SED analysis. However with VLTI/GRAVITY, we made the first observations of a circumplanetary environment with sub-au spatial resolution, placing an upper limit of 0.3~au on the size of a bright disk around PDS 70 b.

Published
2022
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16. Skill Retention and Relearning--A Proposed Cyclical Model.

Author

Ginzburg, S. and Dar-El, E. M.

Abstract

The relationship between relearning and retention was examined during refresher training for 53 Israeli soldiers operating an electronic system. The longer the training interval, the lower the operator's performance level. Partial simulation was suitable for retraining in complex tasks. A cyclical behavior model of learning, forgetting, and relearning was validated. (SK)

Published
2000

18. Constraining the Nature of the PDS 70 Protoplanets with VLTI/GRAVITY ∗

Author

Wang, J. J., Vigan, A., Lacour, S., Nowak, M., Stolker, T., De Rosa, R. J., Ginzburg, S., Gao, P., Abuter, R., Amorim, A., Asensio-Torres, R., Baubck, M., Benisty, M., Berger, J. P., Beust, H., Beuzit, J. -L., Blunt, S., Boccaletti, A., Bohn, A., Bonnefoy, M., Bonnet, H., Brandner, W., Cantalloube, F., Caselli, P., Charnay, B., Chauvin, G., Choquet, E., Christiaens, V., Cl��net, Y., Foresto, V. Coud�� du, Cridland, A., de Zeeuw, P. T., Dembet, R., Dexter, J., Drescher, A., Duvert, G., Eckart, A., Eisenhauer, F., Facchini, S., Gao, F., Garcia, P., Lopez, R. Garcia, Gardner, T., Gendron, E., Genzel, R., Gillessen, S., Girard, J., Haubois, X., Hei��el, G., Henning, T., Hinkley, S., Hippler, S., Horrobin, M., Houll��, M., Hubert, Z., Jim��nez-Rosales, A., Jocou, L., Kammerer, J., Keppler, M., Kervella, P., Meyer, M., Kreidberg, L., Lagrange, A. -M., Lapeyr��re, V., Bouquin, J. -B. Le, L��na, P., Lutz, D., Maire, A. -L., M��nard, F., M��rand, A., Molli��re, P., Monnier, J. D., Mouillet, D., M��ller, A., Nasedkin, E., Ott, T., Otten, G. P. P. L., Paladini, C., Paumard, T., Perraut, K., Perrin, G., Pfuhl, O., Pueyo, L., Rameau, J., Rodet, L., Rodr��guez-Coira, G., Rousset, G., Scheithauer, S., Shangguan, J., Shimizu, T., Stadler, J., Straub, O., Straubmeier, C., Sturm, E., Tacconi, L. J., van Dishoeck, E. F., Vincent, F., von Fellenberg, S. D., Ward-Duong, K., Widmann, F., Wieprecht, E., Wiezorrek, E., Woillez, J., Collaboration, The GRAVITY, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)

Subjects
Gravity (chemistry), 010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Solar and stellar astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Orbit determination, Exoplanet formation, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Earth and planetary astrophysics, Astronomy, Astronomy and Astrophysics, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Protoplanet, Long baseline interferometry 492 487 1175 932, Astrophysics - Earth and Planetary Astrophysics, Exoplanet atmospheres
Abstract

We present K-band interferometric observations of the PDS 70 protoplanets along with their host star using VLTI/GRAVITY. We obtained K-band spectra and 100 $\mu$as precision astrometry of both PDS 70 b and c in two epochs, as well as spatially resolving the hot inner disk around the star. Rejecting unstable orbits, we found a nonzero eccentricity for PDS 70 b of $0.17 \pm 0.06$, a near-circular orbit for PDS 70 c, and an orbital configuration that is consistent with the planets migrating into a 2:1 mean motion resonance. Enforcing dynamical stability, we obtained a 95% upper limit on the mass of PDS 70 b of 10 $M_\textrm{Jup}$, while the mass of PDS 70 c was unconstrained. The GRAVITY K-band spectra rules out pure blackbody models for the photospheres of both planets. Instead, the models with the most support from the data are planetary atmospheres that are dusty, but the nature of the dust is unclear. Any circumplanetary dust around these planets is not well constrained by the planets' 1-5 $\mu$m spectral energy distributions (SEDs) and requires longer wavelength data to probe with SED analysis. However with VLTI/GRAVITY, we made the first observations of a circumplanetary environment with sub-au spatial resolution, placing an upper limit of 0.3~au on the size of a bright disk around PDS 70 b., Comment: 30 pages, 9 figures, Accepted for publication in AJ

Published
2021

19. Constraining the Nature of the PDS 70 Protoplanets with VLTI/GRAVITY ∗ ∗ Based on observations collected at the European Southern Observatory under ESO programmes 0101.C-0281(B), 1103.B-0626(A), 2103.C-5018(A), and 1104.C-0651(A)

Author

Wang, J. J., Vigan, A., Lacour, S., Nowak, M., Stolker, T., De Rosa, R. J., Ginzburg, S., Gao, P., Abuter, R., Amorim, A., Asensio-Torres, R., Bauböck, M., Benisty, M., Berger, J. P., Beust, H., Beuzit, J.-L., Blunt, S., Boccaletti, A., Bohn, A., Bonnefoy, M., Bonnet, H., Brandner, W., Cantalloube, F., Caselli, P., Charnay, B., Chauvin, G., Choquet, E., Christiaens, V., Clénet, Y., Du Foresto, V. Coudé, Cridland, A., Zeeuw, P. T. De, Dembet, R., Dexter, J., Drescher, A., Duvert, G., Eckart, A., Eisenhauer, F., Facchini, S., Gao, F., Garcia, P., Lopez, R. Garcia, Gardner, T., Gendron, E., Genzel, R., Gillessen, S., Girard, J., Haubois, X., Heißel, G., Henning, T., Hinkley, S., Hippler, S., Horrobin, M., Houllé, M., Hubert, Z., Jiménez-Rosales, A., Jocou, L., Kammerer, J., Keppler, M., Kervella, P., Meyer, M., Kreidberg, L., Lagrange, A.-M., Lapeyrère, V., Bouquin, J.-B. Le, Léna, P., Lutz, D., Maire, A.-L., Ménard, F., Mérand, A., Mollière, P., Monnier, J. D., Mouillet, D., Müller, A., Nasedkin, E., Ott, T., Otten, G. P. P. L., Paladini, C., Paumard, T., Perraut, K., Perrin, G., Pfuhl, O., Pueyo, L., Rameau, J., Rodet, L., Rodríguez-Coira, G., Rousset, G., Scheithauer, S., Shangguan, J., Shimizu, T., Stadler, J., Straub, O., Straubmeier, C., Sturm, E., Tacconi, L. J., Dishoeck, E. F. Van, Vincent, F., Fellenberg, S. D. Von, Ward-Duong, K., Widmann, F., Wieprecht, E., Wiezorrek, E., Woillez, J., Collaboration, The GRAVITY, Wang, J. J. [0000-0003-0774-6502], Vigan, A. [0000-0002-5902-7828], Lacour, S. [0000-0002-6948-0263], Stolker, T. [0000-0002-5823-3072], De Rosa, R. J. [0000-0002-4918-0247], Gao, P. [0000-0002-8518-9601], Asensio-Torres, R. [0000-0003-2990-0726], Benisty, M. [0000-0002-7695-7605], Beuzit, J.-L. [0000-0002-7391-479X], Blunt, S. [0000-0002-3199-2888], Bohn, A. [0000-0003-1401-9952], Bonnefoy, M. [0000-0001-5579-5339], Brandner, W. [0000-0003-1939-6351], Caselli, P. [0000-0003-1481-7911], Charnay, B. [0000-0003-0977-6545], Choquet, E. [0000-0002-9173-0740], Christiaens, V. [0000-0002-0101-8814], Clénet, Y. [0000-0002-8382-2020], Zeeuw, P. T. de [0000-0003-4175-3474], Dexter, J. [0000-0003-3903-0373], Eckart, A. [0000-0001-6049-3132], Facchini, S. [0000-0003-4689-2684], Gao, F. [0000-0002-2581-9114], Lopez, R. Garcia [0000-0002-2144-0991], Gardner, T. [0000-0002-3003-3183], Genzel, R. [0000-0002-2767-9653], Gillessen, S. [0000-0002-5708-0481], Girard, J. [0000-0001-8627-0404], Henning, T. [0000-0002-1493-300X], Hinkley, S. [0000-0001-8074-2562], Hippler, S. [0000-0002-3912-6108], Horrobin, M. [0000-0001-5451-7847], Kervella, P. [0000-0003-0626-1749], Meyer, M. [0000-0003-1227-3084], Kreidberg, L. [0000-0003-0514-1147], Bouquin, J.-B. Le [0000-0002-0493-4674], Lutz, D. [0000-0003-0291-9582], Maire, A.-L. [0000-0002-2591-4138], Ménard, F. [0000-0002-1637-7393], Monnier, J. D. [0000-0002-3380-3307], Ott, T. [0000-0003-1572-0396], Paumard, T. [0000-0003-0655-0452], Perrin, G. [0000-0003-0680-0167], Rameau, J. [0000-0003-0029-0258], Rodríguez-Coira, G. [0000-0002-4177-6433], Shangguan, J. [0000-0002-4569-9009], Shimizu, T. [0000-0002-2125-4670], Straub, O. [0000-0001-5755-0677], Straubmeier, C. [0000-0002-0671-9302], Sturm, E. [0000-0002-0018-3666], Tacconi, L. J. [0000-0002-1485-9401], Dishoeck, E. F. van [0000-0001-7591-1907], Vincent, F. [0000-0002-3855-0708], Fellenberg, S. D. von [0000-0002-9156-2249], Ward-Duong, K. [0000-0002-4479-8291], Woillez, J. [0000-0002-2958-4738], and Apollo - University of Cambridge Repository

Subjects
The Solar System, Exoplanets, and Astrobiology, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics
Abstract

We present K-band interferometric observations of the PDS 70 protoplanets along with their host star using VLTI/GRAVITY. We obtained K-band spectra and 100 μas precision astrometry of both PDS 70 b and c in two epochs, as well as spatially resolving the hot inner disk around the star. Rejecting unstable orbits, we found a nonzero eccentricity for PDS 70 b of 0.17 ± 0.06, a near-circular orbit for PDS 70 c, and an orbital configuration that is consistent with the planets migrating into a 2:1 mean motion resonance. Enforcing dynamical stability, we obtained a 95% upper limit on the mass of PDS 70 b of 10 M Jup, while the mass of PDS 70 c was unconstrained. The GRAVITY K-band spectra rules out pure blackbody models for the photospheres of both planets. Instead, the models with the most support from the data are planetary atmospheres that are dusty, but the nature of the dust is unclear. Any circumplanetary dust around these planets is not well constrained by the planets’ 1–5 μm spectral energy distributions (SEDs) and requires longer wavelength data to probe with SED analysis. However with VLTI/GRAVITY, we made the first observations of a circumplanetary environment with sub-astronomical-unit spatial resolution, placing an upper limit of 0.3 au on the size of a bright disk around PDS 70 b.

Published
2021
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20. A Neuroanatomically Grounded Optimal Control Model of the Compensatory Eye Movement System in Mice

Author

Holland, Peter, Sibindi, Tafadzwa, Ginzburg, S, Das, Suman, Arkesteijn, K, Frens, Maarten, Donchin, Opher, Holland, Peter, Sibindi, Tafadzwa, Ginzburg, S, Das, Suman, Arkesteijn, K, Frens, Maarten, and Donchin, Opher

Abstract

We present a working model of the compensatory eye movement system in mice. We challenge the model with a data set of eye movements in mice (n =34) recorded in 4 different sinusoidal stimulus conditions with 36 different combinations of frequency (0.1–3.2 Hz) and amplitude (0.5–8°) in each condition. The conditions included vestibular stimulation in the dark (vestibular-ocular reflex, VOR), optokinetic stimulation (optokinetic reflex, OKR), and two combined visual/vestibular conditions (the visual-vestibular ocular reflex, vVOR, and visual suppression of the VOR, sVOR). The model successfully reproduced the eye movements in all conditions, except for minor failures to predict phase when gain was very low. Most importantly, it could explain the interaction of VOR and OKR when the two reflexes are activated simultaneously during vVOR stimulation. In addition to our own data, we also reproduced the behavior of the compensatory eye movement system found in the existing literature. These include its response to sum-of-sines stimuli, its response after lesions of the nucleus prepositus hypoglossi or the flocculus, characteristics of VOR adaptation, and characteristics of drift in the dark. Our model is based on ideas of state prediction and forward modeling that have been widely used in the study of motor control. However, it represents one of the first quantitative efforts to simulate the full range of behaviors of a specific system. The model has two separate processing loops, one for vestibular stimulation and one for visual stimulation. Importantly, state prediction in the visual processing loop depends on a forward model of residual retinal slip after vestibular processing. In addition, we hypothesize that adaptation in the system is primarily adaptation of this model. In other words, VOR adaptation happens primarily in the OKR loop.

Published
2021

47. Home Air Filtration for Traffic-Related Air Pollution: Study Design and Methods

Author

Brugge, D., primary, Hudda, N., additional, Hersey, S., additional, Meunier, L., additional, Lerman Ginzburg, S., additional, Hochman, I., additional, Echevarria, B., additional, Walker, D., additional, Thanikachalam, M., additional, Sprague Martinez, L., additional, Durant, J., additional, Zamore, W., additional, and Eliasziw, M., additional

Published
2020
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