A5036844792- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Space Exploration and Technology
- Adaptive optics and wavefront sensing
- Astrophysics and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Geophysics and Gravity Measurements
- Particle Detector Development and Performance
- History and Developments in Astronomy
- Dark Matter and Cosmic Phenomena
- Planetary Science and Exploration
- Solar and Space Plasma Dynamics
- Calibration and Measurement Techniques
- Advanced optical system design
- Inertial Sensor and Navigation
- Spacecraft Design and Technology
- Optical Wireless Communication Technologies
- Optical measurement and interference techniques
- Manufacturing Process and Optimization
- Ionosphere and magnetosphere dynamics
Vera C. Rubin Observatory
2022-2024
Pontificia Universidad Católica de Chile
2016-2021
University of Southern Queensland
2019-2021
Millennium Institute of Astrophysics
2017-2019
Ruhr University Bochum
2007-2016
CONTEXT. Exoplanet searches have demonstrated that giant planets are preferentially found around metal-rich stars and their fraction increases with the stellar mass. AIMS. During past six years, we conducted a radial velocity follow-up program of 166 stars, to detect substellar companions, characterizing orbital properties. Using this information, aim study role evolution in parameters unveil possible correlations between properties occurrence rate planets. METHODS. FEROS CHIRON spectra,...
Due to its youth, proximity and richness the Orion Nebula Cloud (ONC) is an ideal testbed obtain a comprehensive view on Initial Mass Function (IMF) down planetary mass regime. Using HAWK-I camera at VLT, we have obtained unprecedented deep wide near-infrared JHK mosaic of ONC (90% completeness K~19.0mag, 22'x28). Applying most recent isochrones accounting for contamination background stars galaxies, find that ONC's IMF bimodal with distinct peaks about 0.25 0.025 M_sun separated by...
We present the discovery of K2-113b, a dense hot-Jupiter discovered using photometry from Campaign 8 Kepler-2 (K2) mission and high-resolution spectroscopic follow up obtained with FEROS spectrograph. The planet orbits $V=13.68$ solar analogue in $P=5.81760^{+0.00003}_{-0.00003}$ day orbit, has radius $0.93^{+0.10}_{-0.07}R_J$ mass $1.29^{+0.13}_{-0.14}M_J$. With density $1.97^{+0.60}_{-0.53}$ gr/cm$^3$, is among densest systems known having masses below 2 $M_J$ $T_{eq} > 1000$, just above...
Abstract We are monitoring a 6° wide stripe along the southern Galactic disk simultaneously in r and i bands, using robotic 15‐cm twin telescope of Universitätsternwarte Bochum near Cerro Armazones Chile. Utilising telescope's 2.7° field view, survey aims at observing mosaic 268 fields once per month to monitor dedicated night. The reaches sensitivity from 10 m down 18 (AB system), with completeness limit ∼ 15.5 14.5 which – due instrumental pixel size 2.″4 refers stars separated by >3″....
We report the discovery of a substellar companion around giant star HIP67537. Based on precision radial velocity measurements from CHIRON and FEROS high-resolution spectroscopic data, we derived following orbital elements for HIP67537$\,b$: m$_b$sin$i$ = 11.1$^{+0.4}_{-1.1}$ M$_{\rm {\tiny jup}}$, $a$ 4.9$^{+0.14}_{-0.13}$ AU $e$ 0.59$^{+0.05}_{-0.02}$. Considering random inclination angles, this object has $\gtrsim$ 65% probability to be above theoretical deuterium-burning limit, thus it is...
SN 2011ja was a bright (I = −18.3) Type II supernova occurring in the nearby edge on spiral galaxy NGC 4945. Flat-topped and multipeaked H α β spectral emission lines appear between 64 84 d post-explosion, indicating interaction with disc-like circumstellar medium inclined ∼45° from edge-on. After day 84, an increase H- K-band flux along heavy attenuation of red wing are strong indications early dust formation, likely located cool dense shell created forward shock ejecta reverse as plows...
Using robotic telescopes of the Universitatssternwarte Bochum near Cerro Armazones in Chile, we monitored z=0.0377 Seyfert 1 galaxy WPVS48 (2MASX J09594263-3112581) optical (B and R) near-infrared (NIR, J Ks) with a cadence two days. The light curves show unprecedented variability details. NIR variation features are consistent corresponding variations, but appear sharper than optical, suggesting that photons undergo multiple scatterings. Ks emission, tracing hot (1600 K) dust echo, lags B R...
We report the discovery of EPIC247098361b using photometric data Kepler K2 satellite coupled with ground-based spectroscopic observations. has a mass M$_{P}=0.397\pm 0.037$ M$_J$, radius R$_{P}=1.00 \pm 0.020$ R$_J$, and moderately low equilibrium temperature $T_{eq}=1030 15$ K due to its relatively large star-planet separation $a=0.1036$ AU. orbits bright ($V=9.9$) late F-type host star in an eccentric orbit ($e=0.258 0.025$) every 11.2 days, is one only four well characterized warm...
Abstract We report the discovery of TOI-677 b, first identified as a candidate in light curves obtained within Sectors 9 and 10 Transiting Exoplanet Survey Satellite ( TESS ) mission confirmed with radial velocities. b has mass <?CDATA ${\text{}}{M}_{{\text{}}p}$?> = ${1.236}_{-0.067}^{+0.069}$?> ${\text{}}{M}_{{\rm{J}}}$?> , radius ${\text{}}{R}_{{\text{}}P}$?> $1.170\pm 0.03$?> ${\text{}}{R}_{{\rm{J}}}$?> orbits its bright host star V 9.8 mag) an orbital period $11.23660\pm 0.00011$?> d,...
We report the discovery of EPIC 201498078b, which was first identified as a planetary candidate from Kepler K2 photometry Campaign 14, and whose nature orbital parameters were then confirmed with precision radial velocities. 201498078b is half massive Saturn ($\rm M_P$=$0.179 \pm 0.021$ $\rm M_J$), has radius R_P$=$0.840 0.011$ R_J$, translates into bulk density $ \rm \rho_P$=$0.37 0.05$ g cm$^{-3}$. transits its slightly evolved G-type host star M_{\star}$=$1.105 0.019$ M_{\odot}$,...
We report the discovery of 24 spectroscopic binary companions to giant stars. fully constrain orbital solution for 6 these systems. cannot unambiguously derive elements remaining stars because phase coverage is incomplete. Of stars, present radial velocity trends that are compatible with long-period brown dwarf companions.The solutions systems indicate have a wide range in periods, eccentricities, and companion masses. For binaries restricted solutions, we find periods between $\sim$ 97-1600...
We report the discovery of two hot Jupiters orbiting stars EPIC229426032 and EPIC246067459. used photometric data from Campaign 11 12 Kepler K2 Mission radial velocity obtained using HARPS, FEROS, CORALIE spectrographs. b EPIC246067459 have masses $1.60^{+0.11}_{-0.11}$ $0.86^{+0.13}_{-0.12}\,M_{\mathrm{Jup}}$, radii $1.65^{+0.07}_{-0.08}$ $1.30^{+0.15}_{-0.14}\,R{_\mathrm{Jup}}$, are their host in 2.18 3.20-day orbits, respectively. The large radius leads us to conclude that this candidate...
We report the discovery of K2-287b, a Saturn mass planet orbiting G-dwarf with period $P \approx 15$ days. First uncovered as candidate using K2 campaign 15 data, follow-up photometry and spectroscopy were used to determine $M_P = 0.317 \pm 0.026$ $M_J$, radius $R_P 0.833 0.013$ $R_J$, 14.893291 0.000025$ days eccentricity $e 0.476 0.026$. The host star is metal-rich $V=11.410 0.129$ mag G dwarf for which we estimate $M_* 1.056$ $M_\odot$, $R_* 1.07 0.01$ $R_\odot$, metallicity [Fe/H] $0.20...
Abstract The new 40cm Bochum Monitoring Telescope (BMT) has started routine operation at the Universitätssternwarte (USB), located near Cerro Armazones in Chile. It a 41′ × 27′ field of view (FoV) and is equipped with B V broad band filters three narrow 670, 680, 690 nm. This makes BMT ideally suited to perform photometric reverberation mapping Hα emission line active galactic nuclei, where redshifted into bands, monitor bright stars which would be saturated large telescopes. As complement...
Although the majority of radial velocity detected planets have been found orbiting solar-type stars, a fraction them discovered around giant stars. These planetary systems revealed different orbital properties when compared to stars companions. In particular, surveys shown that there is lack in close-in orbits contrast known population hot-Jupiters The reason this distinctive feature semimajor-axis distribution has theorized be result stellar evolution and/or due effect formation/evolution...
We report the discovery of two hot Jupiters using photometry from Campaigns 4 and 5 two-wheeled Kepler (K2) mission. K2-30b has a mass $ 0.65 \pm 0.14 M_J$, radius $1.070 0.018 R_J$ transits its G dwarf ($T_{eff} = 5675 50$ K), slightly metal rich ([Fe/H]$=+0.06\pm0.04$ dex) host star in 4.1 days circular orbit. K2-34b 1.63 0.12 $1.38 0.014 an orbital period 3.0 which it orbits late F 6149 55$ K) solar metallicity star. Both planets were validated probabilistically confirmed via precision...
The Multi-Object Optical and Near-Infrared Spectrograph (MOONS) will exploit the full 500 square arcmin field of view offered by Nasmyth focus Very Large Telescope be equipped with two identical triple arm cryogenic spectrographs covering wavelength range 0.64μm-1.8μm, a multiplex capability over 1000 fibres. This can configured to produce spectra for chosen targets have close proximity sky subtraction if required. system both medium resolution (R~4000-6000) mode high (R~20000) mode. fibre...
We present a consistent model atmosphere analysis and evolutionary tracks for the very nearby G-type star 82 Eri that was most recently announced by Pepe et al. to harbour two or three super-Earth companions with orbital periods of 18, 40 90 d.As bright high-velocity object, already realized Jan Hendrik Oort in his 1926 treatise be 'probably different origin' we confirm its being member ancient thick-disc population on account outstanding iron-to-magnesium deficiency.Thus, our immediate...
We present the first results of a comprehensive photometric O-star survey performed with robotic twin refractor at Universitätssternwarte Bochum located near Cerro Armazones in Chile. For three high-mass stars, Pismis 24-1, CPD − 51° 8946, and HD 319702, we determined period through Lafler-Kinman algorithm modelled light curves within framework Roche geometry. previously known eclipsing binary, provide 2.36 days together an orbital inclination 61.8°. The best-fitting model solution to...
Aims. To understand low- to intermediate-mass star-formation in the nearby R Cr A molecular cloud, we try identify stellar content that is accessible with near-infrared observations.
We report about an ongoing photometric and spectroscopic monitoring survey of 250 O- 540 B-type stars in the southern Milky Way with aim to determine fraction close binary systems as a function mass physical parameters individual components multiple systems. Preliminary results suggest that multiplicity rate drops from 80% for highest masses 20% 3 solar masses. Our analysis indicates often contain pairs similar mass. This coincidence cannot originate random tidal capture dense cluster but is...
Context.A long-standing challenge of observational AGN research is to find type 2 quasars, the luminous analogues Seyfert-2 galaxies.
The Multi-Object Optical and Near-infrared Spectrograph (MOONS) will cover the Very Large Telescope's (VLT) field of view with 1000 fibres. fibres be mounted on fibre positioning units (FPU) implemented as two-DOF robot arms to ensure a homogeneous coverage 500 square arcmin view. To accurately fast determine position metrology system has been designed. This paper presents hardware software design performance system. is based analysis images taken by circular array 12 cameras located close...
We present first results of a comprehensive photometric O-star survey performed with robotic twin refractor at the Universit\"atssternwarte Bochum located near Cerro Armazones in Chile. For three high-mass stars, namely Pismis24-1, CPD-518946 and HD319702, we determined period through Lafler-Kinman algorithm model light curves within framework Roche geometry. previously known eclipsing binary, provide 2.36 days together an orbital inclination 61.8 degrees. The best-fitting solution to...