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Parkes observations for project P1229 semester 2023OCTS_08
No full textWe propose a pulsar timing campaign of three millisecond pulsars discovered in previous pulsar searches of Fermi gamma-ray sources. Despite an original follow-up effort, it was not possible to produce a pulsar timing solution with which to detect the expected gamma-ray pulsations. The proposed campaign combines a set of dense, initial observations with additional observations at increasing separation, a bootstrap approach which is generally successful at constraining all the fundamental parameters of the pulsar timing solution. Securing the gamma-ray pulsations will enable probes of the radio and gamma-ray emission mechanisms and searches for multi-wavelength counterparts. And perhaps more importantly, it will allow these pulsars to be incorporated into the gamma-ray pulsar timing array, providing additional baselines which will increase its sensitivity to low-frequency gravitational waves
Parkes observations for project P1171 semester 2023OCTS_13
No full textThe origin of Fast Radio Bursts (FRBs) is still unclear with a plethora of theoretical models for their origin. Several models predict associated multi-wavelength emission, but previous searches for optical, X-ray or gamma-ray counterparts of FRBs have not led to any detection. The Galactic magnetar SGR 1935+2154A has been observed to simultaneously emit FRB-like bursts and X-ray flares, which suggests that also extragalactic FRB sources may exhibit X-ray counterparts.\n \n Because of the high cost of X-ray satellites and in face of the relatively low FRB detection probability in their small field of view, coordinated radio and X-ray observations are logistically very difficult to set up. We propose a new approach using the X-ray satellite XMM-Newton and the Parkes/Murriyang radio telescope to put constraints on the theoretical models: We aim to conduct shadowing observations with the Parkes telescope to search for new FRBs in fields that are simultaneously covered by XMM-Newton. We hereby target regular XMM observations of nearby (low-z) galaxies, to increase our detection chances of possibly associated X-ray emission. In case of an FRB detection in the radio band, we will have guaranteed simultaneous X-ray coverage and will get detailed information about the associated X-ray spectrum and light curve since all XMM-Newton data will become public a year after the observation
Parkes observations for project P1226 semester 2023OCTS_19
No full textFast Radio Bursts(FRBs) are often proposed as useful cosmological probes, however much work is needed to better understand the foreground environment that it propgates through, such as the Galactic ISM and Milky Way Halo. We propose to observe three satellite dwarf spheroidal galaxies of the Milky Way to search for FRBs and pulsars. We plan to take advantage of the new CryoPAF's wide field of view to survey high stellar density dwarf satellite galaxies with substantial angular sizes: Fornax, Sculptor and Sagittarius II. Detections of FRBs and pulsars will allow us to measure the Circumgalactic Medium contribution to FRB dispersion and also the dark matter halos of these dwarf galaxies
Parkes observations for project P1183 semester 2023OCTS_03
No full textWe have detected a total of 48 bursts of FRB 20220529 using the Parkes UWL receiver, with 29 of them detected during full polarization observations. Our previous cooperating observations of FAST and Parkes for FRB 20220529 have revealed significant variations in flux distribution during different active periods. However, only 3 bursts from Parkes have been observed simultaneously with FAST, one of which has the potential to improve the spectrum limits of repeating FRBs by more than an order of magnitude. To further investigate FRB 20220529, we have scheduled regular FAST observations every fortnight, tracking the source for 20 minutes each time. Additionally, we have been granted another 10 hours of FAST time to facilitate simultaneous observations of FRB 20200529 using both the FAST and Parkes telescopes. Therefore, we propose to continue monitoring the source of FRB 20220529 using the Parkes UWL receiver, ensuring high-time resolution and employing full-polarization observations to: (1) detect more bursts using the Parkes UWL receiver, with corresponding simultaneous observations from FAST, in order to obtain robust constraints on the radiation spectrum of repeating FRBs; (2) explore additional clues regarding the active periods of FRB 20220529; (3) study the microstructure of the bursts
Parkes observations for project P1101 semester 2023OCTS_05
No full textWe propose to continue our fortnightly monitoring of a very active repeater, FRB~190520, with the Parkes UWL system. Our current observations show that FRB~190520 is not only the most active FRB that can be observed with Parkes, but also shows extreme rotation measure (RM) variations and unique behavior at 2 to 3 GHz frequency. This makes UWL the ideal instrument to carry out in-depth studies of this repeating FRB. With this program, we expect to detect a large sample of bursts from FRB~190520, and in collaboration with the FAST telescope, we will study the local environment, emission properties, fluence distributions, and polarisation properties over an extremely wide bandwidth with high sensitivity
Parkes observations for project P574 semester 2023OCTS_04
No full textWe request time to observe 260 pulsars on a regular basis in order to provide the accurate ephemerides necessary for the detection and characterisation of gamma-ray pulsars with the Fermi satellite. The main science goals are to increase the number of known gamma-ray pulsars (both radio loud and radio quiet), to determine accurate pulse profiles, and to characterise their high energy (phase-resolved) spectra. In the radio, the observations will also allow us to investigate: neutron stars and pulsar emission via detecting glitches and determining pulse timing parameters; and the ISM via measuring and monitoring dispersion measures, Faraday rotation measures, and scintillation. To date, we are (co-)authors on over 95 papers arising from the collaboration and P574 data, including four which use UWL observations. The data have contributed to the PhD theses of students from Bordeaux, Manchester, Oxford, Stanford, and Swinburne
Parkes observations for project P1211 semester 2023OCTS_03
No full textTraditional pulsar searching techniques are not sensitive enough to extreme pulsars such as millisecond pulsars (MSPs) in compact binaries (e.g., Pulsar-Blackhole binary systems), extremely fast spinning pulsars (e.g., sub-MSPs), and high dispersion measure (DM) pulsars (e.g., pulsars in Galactic Centre and Galactic Plane). Such a situation is now changed thanks to the development of next generation radio telescope arrays such as Australian Square Kilometer Array Pathfinder (ASKAP). ASKAP is capable of conducting highly sensitive radio continuum surveys with wide sky coverage (e.g, Evolutionary Map of The Universe survey). One of the solutions is to find pulsar candidates in radio continuum surveys such as EMU and then carry out targeted searches. This technique allows us to search over the wide bandwidth with full field of view while avoiding the need for expensive pixel-by-pixel high time resolution searches. \n \n In this proposal, we propose to observe 16 MSP candidates identified in the Galactic plane using new ASKAP EMU images. We found 23 candidates by selecting sources with spectral index steeper than -1.90 and compactness less than 1.2. Among them 7 are known pulsars giving us high fraction of pulsars (~33%) and a reasonable number of candidates to follow up (16 sources). Because of the dense ionised medium in the Galactic Plane, MSPs are likely to be missed by previous pulsar surveys carried out at 1.4 GHz. Here, we propose a targeted pulsar search with the Parkes UWL which allow us to search pulsation at higher frequencies and therefore avoid strong DM smearing and scattering effects
Parkes observations for project P1211 semester 2023OCTS_04
No full textTraditional pulsar searching techniques are not sensitive enough to extreme pulsars such as millisecond pulsars (MSPs) in compact binaries (e.g., Pulsar-Blackhole binary systems), extremely fast spinning pulsars (e.g., sub-MSPs), and high dispersion measure (DM) pulsars (e.g., pulsars in Galactic Centre and Galactic Plane). Such a situation is now changed thanks to the development of next generation radio telescope arrays such as Australian Square Kilometer Array Pathfinder (ASKAP). ASKAP is capable of conducting highly sensitive radio continuum surveys with wide sky coverage (e.g, Evolutionary Map of The Universe survey). One of the solutions is to find pulsar candidates in radio continuum surveys such as EMU and then carry out targeted searches. This technique allows us to search over the wide bandwidth with full field of view while avoiding the need for expensive pixel-by-pixel high time resolution searches. \n \n In this proposal, we propose to observe 16 MSP candidates identified in the Galactic plane using new ASKAP EMU images. We found 23 candidates by selecting sources with spectral index steeper than -1.90 and compactness less than 1.2. Among them 7 are known pulsars giving us high fraction of pulsars (~33%) and a reasonable number of candidates to follow up (16 sources). Because of the dense ionised medium in the Galactic Plane, MSPs are likely to be missed by previous pulsar surveys carried out at 1.4 GHz. Here, we propose a targeted pulsar search with the Parkes UWL which allow us to search pulsation at higher frequencies and therefore avoid strong DM smearing and scattering effects
Parkes observations for project P885 semester 2023OCTS_10
No full textWe request a continued modest monitoring cadence of once every 10 days for two radio magnetars, to track their rotation, flux density, and polarisation. 1E 1547.0-5408 has recently suffered a 'hiccup' in radiative properties as well as in its rotation, and the mid-term response to this event remains unclear. Swift J1818.0-1607 remains quite dynamic, and the unique UWL capabilities provide new opportunities to probe still mysterious radio emission mechanisms in magnetars. We will observe XTE J1810-197 and PSR J1622-4950, which ceased emission a year ago, less frequently. The overall request is 18 hours
Parkes observations for project P1219 semester 2023OCTS_17
No full textThe magnetic field potentially regulates the process of star formation and the evolution of molecular clouds. It is inherently difficult to measure interstellar magnetic field strengths, with the measurement of Zeeman splitting a unique method to estimate the magnetic field strength along the line of sight directly. Despite the detection of Zeeman splitting in other mediums, there are as yet no Zeeman detections against compact background sources in quiescent molecular clouds or the cold neutral medium. Pulsars with extremely small solid angles and relatively high transverse velocities are ideal background sources to study the magnetic field in molecular clouds, providing a distinct signal to measure splitting against. There are four pulsars with OH absorption detections, namely PSR B1849+00, B1641-45, B1718-35, and B1749-28. We propose to utilize these four pulsars to explore the properties of the magnetic field and its variations within molecular clouds through both the Zeeman splitting of OH absorption and rotation measure estimations, between epochs. If a detection is confirmed, it will open a new window on the hard-to-measure magnetic fields in molecular clouds, independent of interpretation, thus shedding light on the physics of star formation and the interstellar medium