papers

Publications (32)

astro-ph.IM2016

Optimising a balloon-borne polarimeter in the hard X-ray domain: from the PoGOLite Pathfinder to PoGO+

Maxime Chauvin, Miranda Jackson, Takafumi Kawano +6

PoGOLite is a balloon-borne hard X-ray polarimeter dedicated to the study of point sources. Compton scattered events are registered using an array of plastic scintillator units to…

astro-ph.IM2026

Design and preliminary performance study of the broad-band spectrometer detector for POLAR-2

Jian-Chao Sun, Jiang He, Shuang-Nan Zhang +46

POLAR-2, the successor of the POLAR experiment aboard China's Tiangong-2 space lab, is set to be deployed on the China Space Station. The POLAR-2 mission aims to conducting high-pr…

astro-ph.IM2025

Design and Scientific Prospects of the POLAR-2 Mission

Merlin Kole, Nicolas de Angelis, Jiang He +4

The POLAR-2 mission consists of 3 instruments designed with the combined aim of producing a deeper understanding of Gamma-Ray Bursts. To achieve this, POLAR-2 relies on polarisatio…

astro-ph.IM2025

Design and Performance of a Universal SiPM Readout System for X- and Gamma-Ray Missions

Merlin Kole, Nicolas De Angelis, Nicolas Produit +15

The advent of both multi-messenger and time-domain astrophysics over the last decade has seen a large interest in the development of small-scale, cheap, and robust gamma-ray detect…

astro-ph.IM2018

In-Orbit Instrument Performance Study and Calibration for POLAR Polarization Measurements

Zhengheng Li, Merlin Kole, Jianchao Sun +30

POLAR is a compact space-borne detector designed to perform reliable measurements of the polarization for transient sources like Gamma-Ray Bursts in the energy range 50-500keV. The…

astro-ph.HE2022

Gamma-Ray Polarimetry of the Crab Pulsar Observed by POLAR

Han-Cheng Li, Nicolas Produit, Shuang-Nan Zhang +15

The X/ ray polarimetry of the Crab pulsar/nebula is believed to hold crucial information on their emission models. In the past, several missions have shown evidence of polarize…

physics.ins-det2018

In-flight energy calibration of the space-borne Compton polarimeter POLAR

Hualin Xiao, Wojtek Hajdas, Bobing Wu +39

POLAR is a compact wide-field space-borne detector for precise measurements of the linear polarisation of hard X-rays emitted by transient sources in the energy range from 50 keV t…

astro-ph.IM2013

Balloon-borne hard X-ray polarimetry with PoGOLite

Mark Pearce, Hans-Gustav Florén, Miranda Jackson +8

PoGOLite is a hard X-ray polarimeter operating in the 25-100 keV energy band. The instrument design is optimised for the observation of compact astrophysical sources. Observations…

astro-ph.HE2022

Adding Gamma-ray Polarimetry to the Multi-Messenger Era

Merlin Kole, Francesco Iacovelli, Michele Mancarella +1

The last decade has seen the emergence of two new fields within astrophysics: gamma ray polarimetry and GW astronomy. The former, which aims to measure the polarization of gamma ra…

astro-ph.IM2025

Measurements of the Birks' coefficient of GAGG:Ce using hard X-rays

Merlin Kole, Nicolas De Angelis

Inorganic scintillators continue to be widely used within astrophysical X-ray and gamma-ray detectors. This is in part thanks to the development of new scintillators, such as GAGG:…

astro-ph.IM2018

Polarimetry with POLAR

Merlin Kole

In the first half year of operation the satellite borne POLAR instrument detected a total of 55 Gamma-Ray Bursts about 10 of which were bright enough to allow for detailed polariza…

astro-ph.HE2021

GRB Polarization: A Unique Probe of GRB Physics

Ramandeep Gill, Merlin Kole, Jonathan Granot

Over half a century from the discovery of gamma-ray bursts (GRBs), the dominant radiation mechanism responsible for their bright and highly variable prompt emission remains poorly…

astro-ph.HE2023

Energy-dependent polarization of Gamma-Ray Bursts' prompt emission with the POLAR and POLAR-2 instruments

Nicolas De Angelis, J. Michael Burgess, Franck Cadoux +10

Gamma-Ray Bursts are among the most powerful events in the Universe. Despite half a century of observations of these transient sources, many open questions remain about their natur…

astro-ph.IM2022

Temperature dependence of radiation damage annealing of Silicon Photomultipliers

Nicolas De Angelis, Merlin Kole, Franck Cadoux +9

The last decade has increasingly seen the use of silicon photomultipliers (SiPMs) instead of photomultiplier tubes (PMTs). This is due to various advantages of the former on the la…

astro-ph.HE2025

Gamma-Ray Burst Polarimetry with the POLAR and POLAR-2 missions

Nicolas De Angelis, Philipp Azzarello, Franck Cadoux +15

Gamma-Ray Bursts are among the most powerful and violent events in the Universe. Despite over half a century of observations of these transient sources, many open questions remain…

astro-ph.IM2023

HAGRID -- High Accuracy GRB Rapid Inference with Deep learning

Merlin Kole, Gilles Koziol, David Droz

Since their discoveries in 1967, Gamma-Ray Bursts (GRBs) continue to be one of the most researched objects in astrophysics. Multi-messenger observations are key to gaining a deeper…

astro-ph.IM2014

A Model of the Cosmic Ray Induced Atmospheric Neutron Environment

Merlin Kole, Mark Pearce, Maria Muñoz Salinas

In order to optimise the design of space instruments making use of detection materials with low atomic numbers, an understanding of the atmospheric neutron environment and its depe…

astro-ph.HE2024

Synchrotron polarization of a hybrid distribution of relativistic thermal and nonthermal electrons in GRB prompt emission

Kangfa Cheng, Jirong Mao, Xiaohong Zhao +4

Synchrotron polarization of relativistic nonthermal electrons in gamma-ray bursts (GRBs) has been widely studied. However, recent numerical simulations of relativistic shocks and m…

astro-ph.HE2026

Refined Constraints on the Hard X-ray Polarization of the Crab Pulsar and Nebula Derived from an Extended XL-Calibur Dataset

Matthew G. Baring, Jacob Casey, Sohee Chun +26

We present updated hard X-ray polarization measurements of the Crab pulsar and nebula obtained with the balloon-borne polarimeter XL-Calibur in the ~19-64 keV energy range. During…

astro-ph.IM2024

Optimizing the light output of a plastic scintillator and SiPM based detector through optical characterization and simulation: A case study for POLAR-2

Nicolas De Angelis, Franck Cadoux, Coralie Husi +2

The combination of plastic scintillators with Silicon Photo-Multipliers (SiPMs) is widely used for detecting radiation in high-energy astrophysics, particle physics, neutrino physi…

astro-ph.IM2022

Proton Irradiation of SiPM arrays for POLAR-2

Slawomir Mianowski, Nicolas De Angelis, Johannes Hulsman +12

POLAR-2 is a space-borne polarimeter, built to investigate the polarization of Gamma-Ray Bursts and help elucidate their mechanisms. The instrument is targeted for launch in 2024 o…

astro-ph.IM2019

Phase-resolved gamma-ray spectroscopy of the Crab pulsar observed by POLAR

Han-Cheng Li, Neal Gauvin, Ming-Yu Ge +15

The POLAR detector is a space based Gamma-Ray Burst (GRB) polarimeter sensitive in the 15-500 keV energy range. Apart from its main scientific goal as a Gamma-Ray Burst polarimeter…

astro-ph.IM2022

Gamma-ray Polarimetry of Transient Sources with POLAR

Merlin Kole, Jianchao Sun

Polarization measurements of the gamma-ray component of transient sources are of great scientific interest, they are however, also highly challenging. This is due to the typical lo…

astro-ph.EP2021

Re-evaluation of Lunar X-ray observations by Apollo 15 & 16

Anniek J. Gloudemans, Erik Kuulkers, Riccardo Campana +3

The Apollo 15 & 16 missions were the first to explore the Lunar surface chemistry by investigating about 10% of the Lunar surface using a remote sensing X-ray fluorescence spectrom…

astro-ph.HE2019

Detailed polarization measurements of the prompt emission of five Gamma-Ray Bursts

Shuang-Nan Zhang, Merlin Kole, Tian-Wei Bao +37

Gamma-ray bursts are the strongest explosions in the Universe since the Big Bang, believed to be produced either in forming black holes at the end of massive star evolution or merg…

astro-ph.IM2013

A Balloon-borne Measurement of High Latitude Atmospheric Neutrons Using a LiCAF Neutron Detector

Merlin Kole, Yasushi Fukazawa, Kentaro Fukuda +12

PoGOLino is a scintillator-based neutron detector. Its main purpose is to provide data on the neutron flux in the upper stratosphere at high latitudes at thermal and nonthermal ene…

astro-ph.IM2024

Response of the first POLAR-2 Prototype to Polarized Beams

Merlin Kole, Nicolas de Angelis, Ana Bacelj +15

POLAR-2 is a dedicated gamma-ray polarimeter currently foreseen to be launched towards the China Space Station around 2027. The design of the detector is based on the legacy of its…

astro-ph.IM2014

PoGOLino: a scintillator-based balloon-borne neutron detector

Merlin Kole, Maxime Chauvin, Yasushi Fukazawa +12

PoGOLino is a balloon-borne scintillator-based experiment developed to study the largely unexplored high altitude neutron environment at high geomagnetic latitudes. The instrument…

astro-ph.IM2023

POLAR-2, the next generation of GRB polarization detector

Nicolas Produit, Merlin Kole, Xin Wu +9

The POLAR-2 Gamma-Ray Burst (GRB) Polarimetry mission is a follow-up to the successful POLAR mission. POLAR collected six months of data in 2016-2017 on board the Tiangong-2 Chines…

astro-ph.HE2020

The POLAR Gamma-Ray Burst Polarization Catalog

Merlin Kole, Nicolas De Angelis, Francesco Berlato +18

Despite over 50 years of research, many open questions remain about the origin and nature of GRBs. Polarization measurements of the prompt emission of these extreme phenomena have…

astro-ph.IM2024

Future Perspectives for Gamma-ray Burst Detection from Space

Enrico Bozzo, Lorenzo Amati, Wayne Baumgartner +35

Since their first discovery in the late 1960s, Gamma-ray bursts have attracted an exponentially growing interest from the international community due to their central role in the m…

physics.ins-det2025

Low-temperature Performance of :Ce Scintillators

Merlin Kole, Kasun Wimalasena, Richard Gorby +3

The last years have seen the first cryogenic detectors to be proposed for usage on balloon-borne missions. In such missions, the instrument will be exposed to the high radiation en…