Inter-calibration of atmospheric Cherenkov telescopes with UAV-based airborne calibration system (2022)
Journal Article
Brown, A. M., Muller, J., de Naurois, M., & Clark, P. (2022). Inter-calibration of atmospheric Cherenkov telescopes with UAV-based airborne calibration system. Astroparticle Physics, 140, Article 102695. https://doi.org/10.1016/j.astropartphys.2022.102695

The recent advances in the flight capability of remotely piloted aerial vehicles (here after referred to as UAVs) have afforded the astronomical community the possibility of a new telescope calibration technique: UAV-based calibration. Building upon... Read More about Inter-calibration of atmospheric Cherenkov telescopes with UAV-based airborne calibration system.

Gadolinium loaded Cherenkov detectors for neutron monitoring in high energy air showers (2022)
Journal Article
Stowell, P., Fargher, S., Thompson, L., Brown, A., & Chadwick, P. (2022). Gadolinium loaded Cherenkov detectors for neutron monitoring in high energy air showers. Journal of Instrumentation, 17(02), https://doi.org/10.1088/1748-0221/17/02/t02005

Monitoring of high energy cosmic ray neutrons is of particular interest for cosmic ray water Cherenkov detectors as intense bundles of delayed neutrons have been found to arrive after the initial passage of a high energy air shower. In this paper we... Read More about Gadolinium loaded Cherenkov detectors for neutron monitoring in high energy air showers.

Trinity: An Imaging Air Cherenkov Telescope to Search for Ultra-High-Energy Neutrinos (2021)
Conference Proceeding
Brown, A. M., Bagheri, M., Doro, M., Gazda, E., Kieda, D., Lin, C., …Wang, A. (2021). Trinity: An Imaging Air Cherenkov Telescope to Search for Ultra-High-Energy Neutrinos. In A. Kappes, & B. Keilhauer (Eds.), Proceedings of Science: ICRC 2021

Earth-skimming neutrinos are those which travel through the Earth’s crust at a shallow angle. For Ultra-High-Energy (E휈 > 1 PeV; UHE) earth-skimming tau neutrinos, there is a high-probability that the tau lepton created by a neutrino-Earth interacti... Read More about Trinity: An Imaging Air Cherenkov Telescope to Search for Ultra-High-Energy Neutrinos.

Photohadronic modelling of the 2010 gamma-ray flare from Mrk 421 (2020)
Journal Article
Rosales de León, A., Brown, A. M., & Chadwick, P. M. (2021). Photohadronic modelling of the 2010 gamma-ray flare from Mrk 421. Monthly Notices of the Royal Astronomical Society, 501(2), 2198-2208. https://doi.org/10.1093/mnras/staa3839

Blazars are a subclass of active galactic nuclei (AGNs) that have a relativistic jet with a small viewing angle towards the observer. Recent results based on hadronic scenarios have motivated an ongoing discussion of how a blazar can produce high ene... Read More about Photohadronic modelling of the 2010 gamma-ray flare from Mrk 421.

Locating the gamma-ray emission region in the brightest Fermi-LAT Flat Spectrum Radio Quasars (2020)
Journal Article
Acharyya, A., Chadwick, P. M., & Brown, A. M. (2021). Locating the gamma-ray emission region in the brightest Fermi-LAT Flat Spectrum Radio Quasars. Monthly Notices of the Royal Astronomical Society, 500(4), 5297-5321. https://doi.org/10.1093/mnras/staa3483

We present a temporal and spectral analysis of the gamma-ray flux from nine of the brightest flat-spectrum radio quasars (FSRQs) detected with the Fermi Large Area Telescope during its first 8 yr of operation, with the aim of constraining the locatio... Read More about Locating the gamma-ray emission region in the brightest Fermi-LAT Flat Spectrum Radio Quasars.

Robust diffraction-limited near-infrared-to-near-ultraviolet wide-field imaging from stratospheric balloon-borne platforms—Super-pressure Balloon-borne Imaging Telescope performance (2020)
Journal Article
Romualdez, L. J., Benton, S. J., Brown, A. M., Clark, P., Damaren, C. J., Eifler, T., …Tam, S. (2020). Robust diffraction-limited near-infrared-to-near-ultraviolet wide-field imaging from stratospheric balloon-borne platforms—Super-pressure Balloon-borne Imaging Telescope performance. Review of Scientific Instruments, 91(3), Article 034501. https://doi.org/10.1063/1.5139711

At a fraction of the total cost of an equivalent orbital mission, scientific balloon-borne platforms, operating above 99.7% of the Earth’s atmosphere, offer attractive, competitive, and effective observational capabilities—namely, space-like seeing,... Read More about Robust diffraction-limited near-infrared-to-near-ultraviolet wide-field imaging from stratospheric balloon-borne platforms—Super-pressure Balloon-borne Imaging Telescope performance.

A search for Centaurus A-like features in the spectra of Fermi-LAT detected radio galaxies (2020)
Journal Article
Rulten, C. B., Brown, A. M., & Chadwick, P. M. (2020). A search for Centaurus A-like features in the spectra of Fermi-LAT detected radio galaxies. Monthly Notices of the Royal Astronomical Society, 492(2), 4666-4679. https://doi.org/10.1093/mnras/staa054

Motivated by the detection of a hardening in the γ-ray spectrum of the radio galaxy CentaurusA, we have analysed ∼10 years of Fermi-LAT observations of 26 radio galaxies to search for similar spectral features. We find that the majority of the radio... Read More about A search for Centaurus A-like features in the spectra of Fermi-LAT detected radio galaxies.

Reply to “Comment on ‘Understanding the γ -ray emission from the globular cluster 47 Tuc: Evidence for dark matter?”’ (2019)
Journal Article
Brown, A. M., Lacroix, T., Lloyd, S., Bœhm, C., & Chadwick, P. (2019). Reply to “Comment on ‘Understanding the γ -ray emission from the globular cluster 47 Tuc: Evidence for dark matter?”’. Physical Review D, 100(6), Article 068302. https://doi.org/10.1103/physrevd.100.068302

Analyzing nine years of Fermi-LAT observations, we recently studied the spectral properties of the prominent globular cluster [Phys. Rev. 98, 041301 (2018)]. In particular, we investigated several models to explain the observed gamma-ray emission, ra... Read More about Reply to “Comment on ‘Understanding the γ -ray emission from the globular cluster 47 Tuc: Evidence for dark matter?”’.

An open source toolkit for the tracking, termination and recovery of high altitude balloon flights and payloads (2019)
Journal Article
Clark, P., Funk, M., Funk, B., Funk, T., Meadows, R., Brown, A., …Netterfield, C. (2019). An open source toolkit for the tracking, termination and recovery of high altitude balloon flights and payloads. Journal of Instrumentation, 14(04), Article P04003. https://doi.org/10.1088/1748-0221/14/04/p04003

We present an open source toolkit of flight-proven electronic devices which can be used to track, terminate and recover high altitude balloon flights and payloads. Comprising a beacon, pyrotechnic and non-pyrotechnic cut-down devices plus associated... Read More about An open source toolkit for the tracking, termination and recovery of high altitude balloon flights and payloads.

Understanding the γ-ray emission from the globular cluster 47 Tuc: Evidence for dark matter? (2018)
Journal Article
Brown, A. M., Lacroix, T., Lloyd, S., Bœhm, C., & Chadwick, P. (2018). Understanding the γ-ray emission from the globular cluster 47 Tuc: Evidence for dark matter?. Physical Review D, 98(4), Article 041301(R). https://doi.org/10.1103/physrevd.98.041301

47 Tuc was the first globular cluster observed to be γ -ray bright, with the γ rays being attributed to a population of unresolved millisecond pulsars (MSPs). Recent kinematic data combined with detailed simulations appear to be consistent with the p... Read More about Understanding the γ-ray emission from the globular cluster 47 Tuc: Evidence for dark matter?.

On the prospects of cross-calibrating the Cherenkov Telescope Array with an airborne calibration platform (2017)
Journal Article
Brown, A. M. (2018). On the prospects of cross-calibrating the Cherenkov Telescope Array with an airborne calibration platform. Astroparticle Physics, 97, 69-79. https://doi.org/10.1016/j.astropartphys.2017.10.013

Recent advances in unmanned aerial vehicle (UAV) technology have made UAVs an attractive possibility as an airborne calibration platform for astronomical facilities. This is especially true for arrays of telescopes spread over a large area such as th... Read More about On the prospects of cross-calibrating the Cherenkov Telescope Array with an airborne calibration platform.

Fermi-LAT high-z active galactic nuclei and the extragalactic background light (2017)
Journal Article
Armstrong, T., Brown, A. M., & Chadwick, P. M. (2017). Fermi-LAT high-z active galactic nuclei and the extragalactic background light. Monthly Notices of the Royal Astronomical Society, 470(4), 4089-4098. https://doi.org/10.1093/mnras/stx1309

Observations of distant gamma-ray sources are hindered by the presence of the extragalactic background light (EBL). In order to understand the physical processes that result in the observed spectrum of sources, it is imperative that a good understand... Read More about Fermi-LAT high-z active galactic nuclei and the extragalactic background light.

Prospects for Cherenkov Telescope Array Observations of the Young Supernova Remnant RX J1713.7−3946 (2017)
Journal Article
Acero, F., Aloisio, R., Amans, J., Amato, E., Antonelli, L., Aramo, C., …Zorn, J. (2017). Prospects for Cherenkov Telescope Array Observations of the Young Supernova Remnant RX J1713.7−3946. Astrophysical Journal, 840(2), Article 74. https://doi.org/10.3847/1538-4357/aa6d67

We perform simulations for future Cherenkov Telescope Array (CTA) observations of RX J1713.7−3946, a young supernova remnant (SNR) and one of the brightest sources ever discovered in very high energy (VHE) gamma rays. Special attention is paid to exp... Read More about Prospects for Cherenkov Telescope Array Observations of the Young Supernova Remnant RX J1713.7−3946.

Discovery of a new extragalactic population of energetic particles (2017)
Journal Article
Brown, A. M., Bœhm, C., Graham, J., Lacroix, T., Chadwick, P., & Silk, J. (2017). Discovery of a new extragalactic population of energetic particles. Physical Review D, 95(6), Article 063018. https://doi.org/10.1103/physrevd.95.063018

Gamma-ray Novae: Rare or Nearby? (2016)
Journal Article
Morris, P., Cotter, G., Brown, A., & Chadwick, P. (2017). Gamma-ray Novae: Rare or Nearby?. Monthly Notices of the Royal Astronomical Society, 465(1), 1218-1226. https://doi.org/10.1093/mnras/stw2776

Classical novae were revealed as a surprise source of γ-rays in Fermi Large Area Telescope (LAT) observations. During the first 8 yr since the LAT was launched, 6 novae in total have been detected to >5σ in γ-rays, in contrast to the 69 discovered op... Read More about Gamma-ray Novae: Rare or Nearby?.

The GCT camera for the Cherenkov Telescope Array (2016)
Conference Proceeding
Brown, A., Abchiche, A., Allan, D., Amans, J., Armstrong, T., Balzer, A., …Zorn, J. (2016). The GCT camera for the Cherenkov Telescope Array. In H. J. Hall, R. Gilmozzi, & H. K. Marshall (Eds.), Ground-Based and Airborne Telescopes VI : 26 June-1 July 2016, Edinburgh, United Kingdom. https://doi.org/10.1117/12.2231685

The Gamma-ray Cherenkov Telescope (GCT) is proposed for the Small-Sized Telescope component of the Cherenkov Telescope Array (CTA). GCT's dual-mirror Schwarzschild-Couder (SC) optical system allows the use of a compact camera with small form-factor p... Read More about The GCT camera for the Cherenkov Telescope Array.

Localizing the γ-ray emission region during the 2014 June outburst of 3C 454.3 (2016)
Journal Article
Coogan, R. T., Brown, A. M., & Chadwick, P. M. (2016). Localizing the γ-ray emission region during the 2014 June outburst of 3C 454.3. Monthly Notices of the Royal Astronomical Society, 458(1), 354-365. https://doi.org/10.1093/mnras/stw199

In 2014 May–July, the flat spectrum radio quasar 3C 454.3 exhibited strong flaring behaviour. Observations with the Large Area Telescope detector on-board the Fermi Gamma-ray Space Telescope captured the γ-ray flux at energies 0.1 ≤ Eγ ≤ 300 GeV incr... Read More about Localizing the γ-ray emission region during the 2014 June outburst of 3C 454.3.

The detection of Fermi AGN above 100 GeV using clustering analysis (2015)
Journal Article
Armstrong, T., Brown, A. M., Chadwick, P., & Nolan, S. (2015). The detection of Fermi AGN above 100 GeV using clustering analysis. Monthly Notices of the Royal Astronomical Society, 452(3), 3159-3166. https://doi.org/10.1093/mnras/stv1398

The density-based clustering algorithm DBSCAN has been applied to the Fermi Large Area Telescope (LAT) data set of Eγ ≥ 100 GeV events with |b| > 10°, in order to search for new very high energy (VHE) γ-ray sources. The clustering analysis returned 4... Read More about The detection of Fermi AGN above 100 GeV using clustering analysis.

γ-ray observations of extraterrestrial neutrino track events (2015)
Journal Article
Brown, A. M., Adams, J., & Chadwick, P. M. (2015). γ-ray observations of extraterrestrial neutrino track events. Monthly Notices of the Royal Astronomical Society, 451(1), 323-331. https://doi.org/10.1093/mnras/stv899

In this paper we report the results of a γ-ray study of IceCube's extraterrestrial neutrino candidates detected as track-like events. Using 70 months of Fermi-Large Area Telescope (LAT) observations, a likelihood analysis of all 1–300 GeV photons wit... Read More about γ-ray observations of extraterrestrial neutrino track events.

Very high energy γ-ray emission from RBS 0679 (2014)
Journal Article
Brown, A. M., Chadwick, P. M., & Landt, H. (2014). Very high energy γ-ray emission from RBS 0679. Monthly Notices of the Royal Astronomical Society, 445(4), 4345-4350. https://doi.org/10.1093/mnras/stu2321

In this paper, we report the Fermi Large Area Telescope (LAT) detection of Very High Energy (VHE; Eγ > 100 GeV) γ-ray emission from the BL Lac object RBS 0679. 5.3 years of LAT observations revealed the presence of three VHE photon events within 0 ∘.... Read More about Very high energy γ-ray emission from RBS 0679.