A5024111134- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Astrophysical Phenomena and Observations
- History and Developments in Astronomy
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Atmospheric Ozone and Climate
- Trypanosoma species research and implications
- Geophysics and Gravity Measurements
- Climate variability and models
- Biochemical and Molecular Research
- Geology and Paleoclimatology Research
- Inertial Sensor and Navigation
- Spectroscopy and Laser Applications
- Spectroscopy Techniques in Biomedical and Chemical Research
- Viral gastroenteritis research and epidemiology
- Pulsars and Gravitational Waves Research
- Respiratory viral infections research
- Virus-based gene therapy research
- SARS-CoV-2 detection and testing
- Research on Leishmaniasis Studies
German Cancer Research Center
2018-2022
Heidelberg University
2018-2022
Biology of Infection
2020
Universität Hamburg
2008-2019
Hamburger Fern-Hochschule
2004-2014
Leibniz Institute for Astrophysics Potsdam
1980-1997
Rosa Luxemburg Foundation
1986-1991
Konkoly Observatory
1991
Hungarian Academy of Sciences
1991
University of Wrocław
1980
Abstract During the ongoing COVID-19 pandemic, PCR testing and antigen tests have proven critical for helping to stem spread of its causative agent, SARS-CoV-2. However, these methods suffer from either general applicability and/or sensitivity. Moreover, emergence variant strains creates need flexibility correctly efficiently diagnose presence substrains. To address needs we developed diagnostic test ADESSO (Accurate Detection Evolving SARS-CoV-2 through SHERLOCK (Specific High Sensitivity...
Abstract TIGRE is a new robotic spectroscopy telescope located in central Mexico at the La Luz Observatory of University Guanajuato. The 1.2 m fiber‐coupled to an ´echelle spectrograph with spectral resolving power exceeding 20000 over most covered range between 3800 Å and 8800 Å, small gap 130 around 5800 Å. operates robotically, i.e. it (normally) carries out all observations without any human intervention, including, particular, target selection given observing night. In this paper we...
Abstract. The longest six instrumental temperature records of monthly means reach back maximally to 1757 AD and were recorded in Europe. All show a V-shape, with drop the 19th rise 20th century. Proxy time series Antarctic ice cores this same characteristic shape, indicating pattern as global phenomenon. We used mean for analysis by discrete Fourier transform (DFT), wavelets, detrended fluctuation (DFA). For comparison, stalagmite record was also analyzed DFT. harmonic decomposition...
Probing the structures of stellar winds is prime importance for understanding massive stars. Based on their optical spectral morphology and variability, stars Oef class have been suggested to feature large-scale in wind. High-resolution X-ray spectroscopy time-series observations presumably-single O-type can help us understand physics winds. We collected XMM-Newton coordinated O6Ief star lambda Cep study its variability analyse high-resolution spectrum. investigate line profile He II 4686...
Aims. A large number of Calcium Infrared Triplet (IRT) spectra are expected from the GAIA- and CARMENES missions. Conversion these into known activity indicators will allow analysis their temporal evolution to a better degree. We set out find such conversion formula determine its robustness. Methods. have compared 2274 Ca II IRT active main-sequence F K stars taken by TIGRE telescope with those inactive same spectral type. After normalizing applying rotational broadening, we subtracted...
Context. The rotation period of a star is key parameter both for the stellar dynamo that generates magnetic fields as well differential rotation.
The discovery of vulnerable regions on norovirus particles is instrumental in the development effective inhibitors, particularly for GI noroviruses that are genetically diverse. Analysis these GI.1-specific Nanobodies has shown similar to GII particles, have regions. only known cofactor region, HBGA binding pocket, represents main target inhibition. With a combination treatment, i.e., addition Nano-7 or Nano-94 with 2′FL, effect inhibition was increased. Therefore, drug treatments might...
Context.While the existence of stellar analogues 11 years solar activity cycle is proven for dozens stars from optical observations chromospheric activity, observation clearly cyclical coronal still in its infancy.
We relate the evolutionary status and mass of Mt. Wilson project stars with type strength stellar activity as established in decades monitoring their chromospheric Ca II K line emission. specifically derive positions Hertzsprung-Russell-diagram (HRD) from Hipparcos parallaxes SIMBAD B − V data, considering correcting for effects different individual metallicities, place groups on a common set Z = 0.02 evolution tracks to obtain quantitative picture relative distribution. find that, first,...
Abstract. A large number of investigations paleoclimate have noted the influence a ~ 200 year oscillation which has been related to De Vries/Suess cycle solar activity. As such studies were concerned mostly with local climate, we used extensive northern hemispheric proxy data sets Büntgen and Christiansen/Ljungqvist together southern tree-ring set, all 1 time resolution, analyze climate cycle. there is increasing interest in temperature rise rates, as opposed present absolute temperatures,...
We have used our robotic TIGRE facility to closely monitor the star τ Boo during last three observing seasons 2013–2016 and determine its S-index variability from strength of Ca ii H K line cores in order study characteristic cyclic chromospheric variations rotation period. furthermore reanalyze archival X-ray data taken with XMM-Newton satellite. Using Lomb-Scargle periodograms, we find a strong periodic signal period about 122 days extremely high significance, which is also consistent...
The activity levels of the solar-twin candidates HD 101364 and 197027 are measured compared with Sun, known solar twin 18 Sco, solar-like star 51 Peg. Furthermore, absolute ages these five objects estimated from their positions in HR diagram evolutionary (relative) age levels. To represent level stars, Mount Wilson S-indices were used. obtain consistent advance on main sequence, we used tracks calculated Cambridge Stellar Evolution Code. From our spectroscopic observations based established...
Aims. Previous studies have shown that, for late-type stars, activity indicators derived from the Ca ii infrared-triplet (IRT) lines are correlated with H&K lines. Therefore, IRT in principle usable studies, but they may be less sensitive when measuring rotation period. Our goal is to determine whether sufficiently measure periods and how any compare “classical” Mount Wilson S-index.
The fully automatic reduction pipeline for the blue channel of HEROS spectrograph Hamburg Robotic Telescope (HRT) is presented. This started automatically after finishing night‐time observations and calibrations. includes all necessary procedures a reliable complete data reduction, that is, Bias, Dark, Flat Field correction. Also order definition, wavelength calibration, extraction are included. final output written in fits‐format ready to use astronomer. implemented IDL based on package...
We present a time series of high resolution spectra the Type Ia supernova 2014J, which exploded in nearby galaxy M82. The were obtained with HEROS echelle spectrograph installed at 1.2 m TIGRE telescope. 33 R = 20, 000, covers important bright phases evolution SN 2014J during period from January 24 to April 1 2014. spectral is derived empirically. expansion velocities Si II P-Cygni features measured and show expected decreasing behaviour, beginning velocity 14,000 km/s on 24. Ca infrared...
Previous studies have revealed a 120 day activity cycle in the F-type star τ Boo, which represents shortest discovered until now. The question arises as to whether or not short-term cycles are common phenomenon stars. To address this question, we analyse S -index time series of stars taken with TIGRE telescope search for periodic variations maximal length 2 years using generalised Lomb-Scargle periodogram method. In our sample, find four showing shorter than one year. However, amplitude...
A growing number of Be and Oe stars, named the gamma Cas are known for their unusually hard intense X-ray emission. This emission could either trace accretion by a compact companion or magnetic interaction between star its decretion disk. To test these scenarios, we carried out detailed optical monitoring HD45314, hottest member class along with dedicated observations on specific dates. High-resolution spectra were taken to monitor lines formed in disk, while spectroscopy was obtained at...
The dense variant surface glycoprotein (VSG) coat of African trypanosomes represents the primary host-pathogen interface. Antigenic variation prevents clearing pathogen by employing a large repertoire antigenically distinct VSG genes, thus neutralizing host's antibody response. To explore epitope space VSGs, we generate anti-VSG nanobodies and combine high-resolution structural analysis VSG-nanobody complexes with binding assays on living cells, revealing that these camelid antibodies bind...
Abstract Ten‐colour photoelectric observations are presented for twelve Ap‐stars. Improved ephemeris seven of them is given. Phase relations between the light curves and line intensity variations discussed. The problem electromagnetic flux conctancy IOTA Cas approached from a qualitative point view.
We present a new radial velocity curve for the two components of eclipsing spectroscopic binary α CrB. This consists main-sequence stars types A and G in 17.3599-day orbit, according to data from our robotic TIGRE facility that is located Guanajuato, Mexico. used high-resolution solar spectrum determine velocities weak secondary component by cross-correlation wavelength referencing with telluric lines strongly rotationally broadened primary (v sin(i) = 138 km s-1) obtain an accuracy few...
We investigate a four-and-one-half year time-series of ROSAT HRI pointed observations 61 Cyg A and B compare the X-ray light curves with chromospheric Ca HK variability. The sampling rate was two pointings per typical errors lie in range 5–10%. cycles are well-known for both stars from Mt. Wilson survey. Although time basis our is shorter than 7-and 12-year components B, respectively, we find long-term trend coronal activity close correlation during observation period, between 1993 1998....
Aims. We investigate the early development of classical nova V339 Del (Nova Delphini 2013) through high-resolution optical spectroscopy. To study structure ejecta, we focus on evolution absorption and emission features changes within line profiles.