A5000065320- Solar and Space Plasma Dynamics
- Radio Astronomy Observations and Technology
- Ionosphere and magnetosphere dynamics
- Astrophysics and Cosmic Phenomena
- Geophysics and Gravity Measurements
- GNSS positioning and interference
- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- High-Energy Particle Collisions Research
- Stellar, planetary, and galactic studies
- earthquake and tectonic studies
- Particle physics theoretical and experimental studies
- Particle Accelerators and Free-Electron Lasers
- Astrophysics and Star Formation Studies
- Particle accelerators and beam dynamics
- Radio Wave Propagation Studies
- Seismology and Earthquake Studies
- Quantum Chromodynamics and Particle Interactions
- Geomagnetism and Paleomagnetism Studies
- Astronomy and Astrophysical Research
- Seismic Imaging and Inversion Techniques
- History and Developments in Astronomy
- Advanced Frequency and Time Standards
University of Warmia and Mazury in Olsztyn
2015-2024
Uniwersytecki Szpital Kliniczny w Olsztynie
2018
Czech Academy of Sciences
2010-2014
Czech Academy of Sciences, Astronomical Institute
2011
Massachusetts Institute of Technology
2009
ETH Zurich
2009
Polish Academy of Sciences
2008
Netherlands Institute for Radio Astronomy
2005
Nicolaus Copernicus University
2005
Institute of Nuclear Physics, Polish Academy of Sciences
2000-2003
We present the first measurement of pseudorapidity densities primary charged particles near midrapidity in Au+Au collisions at sqrt[s(NN)] = 56 and 130 GeV. For most central collisions, we find charged-particle density to be dN/deta|(|eta|<1) 408+/-12(stat)+/-30(syst) GeV 555+/-12(stat)+/-35(syst) GeV, values that are higher than any previously observed nuclear collisions. Compared proton-antiproton our data show an increase per participant by more 40% energy.
Collisionless shocks are one of the most powerful particle accelerators in Universe. In heliosphere, type II solar radio bursts signatures electrons accelerated by collisionless launched at Sun. Spectral observations these show a variety fine structures often composing multiple lanes. The origin lanes and is not well understood has been attributed to inhomogeneous environment around propagating shock. Here, we aim determine large-scale local near coronal shock wave using high-resolution...
Abstract Shock waves in the solar corona are closely associated with coronal mass ejections and flares. The longest-known frequently studied signatures of shock metric type II radio bursts, which provide information on driver ambient plasma conditions. We report outstanding high frequency/time resolution LOw Frequency ARray (LOFAR) observations a burst. LOFAR show strong fragmentation emission, both frequency time domains, during whole duration event. A very unusual splitting an...
Abstract Radio emission of the quiet Sun is considered to be due thermal bremsstrahlung hot solar atmosphere. The properties in microwave band have been well studied, and they can described by spectrum emission. In meter-wave decameter-wave bands, rarely studied instrumental limitations. this work, we use LOw Frequency ARray telescope perform high quality interferometric imaging spectroscopy observations coronal at frequencies below 90 MHz. We present brightness temperature size frequency...
Type II radio bursts are evidence of shocks in the solar atmosphere and inner heliosphere that emit waves ranging from sub-meter to kilometer lengths. These may be associated with CMEs reach speeds higher than local magnetosonic speed. Radio imaging decameter wavelengths (20-90 MHz) is now possible LOFAR, opening a new window which study coronal leave corona enter interplanetary medium understand their association CMEs. To this end, we shock CME type burst determine locations at emission...
This paper presents the results from one of first observations ionospheric scintillation taken using Low-Frequency Array (LOFAR). The observation was strong natural radio source Cassiopeia A, overnight on 18–19 August 2013, and exhibited moderately scattering effects in dynamic spectra intensity received across an observing bandwidth 10–80 MHz. Delay-Doppler (the 2-D FFT spectrum) hour showed two discrete parabolic arcs, with a steep curvature other shallow, which can be used to provide...
Context. The quiet solar corona emits meter-wave thermal bremsstrahlung. Coronal radio emission can only propagate above that radius, R ω , where the local plasma frequency equals observing frequency. interferometer LOw Frequency ARray (LOFAR) observes in its low band (10–90 MHz) originating from middle and upper corona. Aims. We present first aperture synthesis imaging observations of LOFAR 12 frequencies each separated by 5 MHz. From these maps we infer a scale height temperature, T ....
Observations made using the LOw-Frequency ARray (LOFAR) between 10:15 and 11:48 UT on 15th of September 2018 over a bandwidth approximately 25–65 MHz contain discrete pseudo-periodic features ionospheric origin. These occur within period 10 min collectively last roughly an hour. They are strongly frequency dependent, broadening significantly in time towards lower frequencies, show overlaid pattern diffraction fringes. By modelling ionosphere as thin phase screen containing wave-like...
Abstract The large scale morphology and finer sub‐structure within a slowly propagating traveling ionospheric disturbance (TID) are studied using wide band trans‐ionospheric radio observations with the LOw Frequency ARray (LOFAR; van Haarlem et al., 2013, https://doi.org/10.1051/0004-6361/201220873 ). were made under geomagnetically quiet conditions, between 0400 0800 on 7 January 2019, over UK. In combination ionograms Global Navigation Satellite System Total Electron Content anomaly data...
Abstract The Sun is an active star that often produces numerous bursts of electromagnetic radiation at radio wavelengths. Low frequency have recently been brought back to light with the advancement novel interferometers. However, their polarisation properties not yet explored in detail, especially Frequency Array (LOFAR), due difficulties calibrating data and accounting for instrumental leakage. Here, using a unique method correct observations, we explore circular different sub-types solar...
Large coronal loops around one solar radius in altitude are an important connection between the wind and low corona. However, their plasma properties ill-defined as standard X-ray UV techniques not suited to these low-density environments. Diagnostics from type J radio bursts at frequencies above 10 MHz ideally understand loops. Despite this, J-bursts less frequently studied than III cousins, part because curvature of loop makes them unsuited for using density models. We used...
Context. Solar radio bursts originate mainly from high energy electrons accelerated in solar eruptions like flares, jets, and coronal mass ejections. A sub-category of with short time duration may be used as a proxy to understand wave generation propagation within the corona. Aims. Complete case studies source size, position, kinematics term are very rare due instrumental limitations. comprehensive multi-frequency spectroscopic imaging study was carried out clear example type IIIb-III pair....
Context. In the solar corona, shocks can be generated due to pressure pulse of a flare and/or driven by rising coronal mass ejection (CME). Coronal shock waves observed as type II radio bursts in Sun’s radiation. dynamic spectra, they appear stripes an enhanced emission slowly drifting from high low frequencies. The is thought plasma emission, that say happens near electron frequency its harmonics. Plasma means energetic electrons excite Langmuir waves, which convert into via non-linear...
While the surface missions to Moon of 1970s achieved a great deal, scientifically much was also left unresolved. The recent plethora lunar (flown or proposed) reflects resurgence in interest Moon, not only its own right, but as record early solar system including formation Earth. Results from orbiter have shown evidence ice at least hydrogen within shadowed craters poles.
The LOw-Frequency ARray (LOFAR) is a new radio interferometer that consists of an array stations. Each them phase dipole antennas. LOFAR stations are distributed mostly in the Netherlands, but also throughout Europe. In article we discuss possibility using this instrument for solar and space weather studies, as well ionosphere investigations. We expecting near future telescope will bring some interesting observations discoveries these fields. It help to observe active events have direct...
We present here a brief description of thirteen events the narrowband solar millisecond radio spike emissions observed between February 2000 and December 2001. The total observing time was 1990.4 h, collected during 357 days. data were with 15-m telescope fast radiospectrograph Toruń Observatory, Poland. dynamic spectra spikes recorded in 1352-1490 MHz frequency band split into 46 channels temporal resolution equals to 12 500 measurements per second channel. presented observations have...
Context. Observations of solar, type II radio bursts provide a unique opportunity to analyze the nonthermal electrons accelerated by coronal shocks and diagnose plasma density distribution in corona. However, there are very few high-frequency resolution interferometric observations that capable tracking these electrons. Aims. Recently, more spatially resolved high-resolution have been recorded with Low-Frequency Array (LOFAR). Using observations, we aim track location burst experienced...
<i>Aims. <i/>The emission of decimetric flare radiation, in particular narrowband spikes and pulsations, is generally considered to originate accelerated, non-thermal particles. On the other hand, hard X-rays are also understood be products this acceleration. Do radio X-ray signatures from same acceleration process? A strong correlation between light curves HXR ranges may help answer question.<i>Methods. delay was determined by cross-correlation. The time profiles include a wide range...
Radio continuum observations trace thermal emission of ionized plasma in planetary nebulae and bring useful information on nebular geometries. A model homogeneous sphere or shell cannot fit the spectra brightness temperatures. Two alternative models have been proposed literature: first one consists two components, while other is a with significant radial density gradient. On side, prolate ellipsoidal can successfully surface distribution selected objects. We verify existing using data...
LOFAR (LOw Frequency ARray) is a new generation digitally controlled radio telescope consisting of phased array antenna stations with sensitivity, bandwidth, range frequency, and digital processing power that makes it an excellent tool for observations pulsars. This interferometric instrument able to work in single-station mode as well group-of-selected-stations mode. article discusses the great opportunity conducting unique independent research pulsar sources three located Poland maintained...
Numerous solar radio bursts were observed in 2000 – 2001 using the Toruń spectrograph with its unique time resolution of 80 microseconds. This high enables an in-depth analysis evolution power spectra and Fourier spectral indices selected short bursts. We analyze power-spectrum parameters variability for two millisecond dm-spike events one drifting pulsation structure (DPS) event, which structures recorded signals analyzed effective 0.0008 s five adjacent frequency bands their spectra. found...