The H.E.S.S. multi-messenger program

Based on fundamental particle physics processes like the production and subsequent decay of pions in interactions of high-energy particles, close connections exist between the acceleration sites of high-energy cosmic rays and the emission of high-energy gamma rays and high-energy neutrinos. In most cases these connections provide both spatial and temporal correlations of the different emitted particles. The combination of the complementary information provided by these messengers allows to lift ambiguities in the interpretation of the data and enables novel and highly sensitive analyses. In this contribution the H.E.S.S. multi-messenger program is introduced and described. The current core of this newly installed program is the combination of high-energy neutrinos and high-energy gamma rays. The search for gamma-ray emission following gravitational wave triggers is also discussed. Furthermore, the existing program for following triggers in the electromagnetic regime was extended by the search for gamma-ray emission from Fast Radio Bursts (FRBs). An overview over current and planned analyses is given and recent results are presented.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherland

HESS J1826−-130: A Very Hard γ\gamma-Ray Spectrum Source in the Galactic Plane

HESS J1826$-$130 is an unidentified hard spectrum source discovered by H.E.S.S. along the Galactic plane, the spectral index being $\Gamma$ = 1.6 with an exponential cut-off at about 12 TeV. While the source does not have a clear counterpart at longer wavelengths, the very hard spectrum emission at TeV energies implies that electrons or protons accelerated up to several hundreds of TeV are responsible for the emission. In the hadronic case, the VHE emission can be produced by runaway cosmic-rays colliding with the dense molecular clouds spatially coincident with the H.E.S.S. source.Comment: 6 pages, 3 figures, Proceedings of the 6th International Symposium on High Energy Gamma-Ray Astronomy (Gamma2016), Heidelberg, German

The H.E.S.S. II GRB Program

Gamma-ray bursts (GRBs) are some of the most energetic and exotic events in the Universe, however their behaviour at the highest energies (>10 GeV) is largely unknown. Although the Fermi-LAT space telescope has detected several GRBs in this energy range, it is limited by the relatively small collection area of the instrument. The H.E.S.S. experiment has now entered its second phase by adding a fifth telescope of 600 m$^{2}$ mirror area to the centre of the array. This new telescope increases the energy range of the array, allowing it to probe the sub-100 GeV range while maintaining the large collection area of ground based gamma-ray observatories, essential to probing short-term variability at these energies. We will present a description of the GRB observation scheme used by the H.E.S.S. experiment, summarising the behaviour and performance of the rapid GRB repointing system, the conditions under which potential GRB repointings are made and the data analysis scheme used for these observations.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherland

Exome sequencing of an isolated Chilean population affected by Specific Language Impairment (SLI)

Speech and language impairments that are a primary deficit and have no obvious cause (e.g. a comorbid neurological disorder like autism) are diagnosed as Specific Language Impairment (SLI). SLI affects 5–8 % of preschool children and represents a lifelong disability associated with an increased risk of behavioural disorders, social problems and literacy deficits. SLI is highly heritable and twin studies indicate a strong genetic basis. Nonetheless, the underlying genetic mechanisms are expected to be multifactorial and, to date, only three risk variants have been identified. One way to increase the power to detect contributory genetic factors is to study isolated populations derived from relatively recent shared ancestors (founder populations). In 2008, Villanueva described a founder population with a particularly high incidence of SLI (10 times that expected). They inhabit the Robinson Crusoe Island, which lies 677 km to the west of Chile and was colonised in the late 19th century by 8 European and Amerindian families. 77 % of the current island population have a colonising surname and 14 % of marriages involve consanguineous unions. More than 80 % of language impaired individuals can be traced to a pair of founder brothers. This population thus has a short (5-generations) and well documented history and represents a unique resource which could make valuable contributions to the elucidation of genetic mechanisms underpinning SLI. We applied exome sequencing technologies to five language impaired individuals from this population and identified nine nonsynonymous coding changes or splice site mutations that were present in at least three of the five affected individuals sequenced. Sequencing of the entire cohort identified a single non-synonymous coding change that was significantly more frequent in cases than controls (genotype frequencies of 46 and 11 % respectively, p = 4.48 9 10-5). We suggest that this rare coding variant may contribute to the elevated frequency of SLI in this population

Whole-genome sequencing of spermatocytic tumors provides insights into the mutational processes operating in the male germline

Adult male germline stem cells (spermatogonia) proliferate by mitosis and, after puberty, generate spermatocytes that undertake meiosis to produce haploid spermatozoa. Germ cells are under evolutionary constraint to curtail mutations and maintain genome integrity. Despite constant turnover, spermatogonia very rarely form tumors, so-called spermatocytic tumors (SpT). In line with the previous identification of FGFR3 and HRAS selfish mutations in a subset of cases, candidate gene screening of 29 SpTs identified an oncogenic NRAS mutation in two cases. To gain insights in the etiology of SpT and into properties of the male germline, we performed whole-genome sequencing of five tumors (4/5 with matched normal tissue). The acquired single nucleotide variant load was extremely low (~0.2 per Mb), with an average of 6 (2±9) no

Detection of variable VHE gamma-ray emission from the extra-galactic gamma-ray binary LMC P3

Context. Recently, the high-energy (HE, 0.1-100 GeV) $\gamma$-ray emission from the object LMC P3 in the Large Magellanic Cloud (LMC) has been discovered to be modulated with a 10.3-day period, making it the first extra-galactic $\gamma$-ray binary. Aims. This work aims at the detection of very-high-energy (VHE, >100 GeV) $\gamma$-ray emission and the search for modulation of the VHE signal with the orbital period of the binary system. Methods. LMC P3 has been observed with the High Energy Stereoscopic System (H.E.S.S.); the acceptance-corrected exposure time is 100 h. The data set has been folded with the known orbital period of the system in order to test for variability of the emission. Energy spectra are obtained for the orbit-averaged data set, and for the orbital phase bin around the VHE maximum. Results. VHE $\gamma$-ray emission is detected with a statistical significance of 6.4 $\sigma$. The data clearly show variability which is phase-locked to the orbital period of the system. Periodicity cannot be deduced from the H.E.S.S. data set alone. The orbit-averaged luminosity in the $1-10$ TeV energy range is $(1.4 \pm 0.2) \times 10^{35}$ erg/s. A luminosity of $(5 \pm 1) \times 10^{35}$ erg/s is reached during 20% of the orbit. HE and VHE $\gamma$-ray emissions are anti-correlated. LMC P3 is the most luminous $\gamma$-ray binary known so far.Comment: 5 pages, 3 figures, 1 table, accepted for publication in A&

Characterizing the gamma-ray long-term variability of PKS 2155-304 with H.E.S.S. and Fermi-LAT

Studying the temporal variability of BL Lac objects at the highest energies provides unique insights into the extreme physical processes occurring in relativistic jets and in the vicinity of super-massive black holes. To this end, the long-term variability of the BL Lac object PKS 2155-304 is analyzed in the high (HE, 100 MeV 200 GeV) gamma-ray domain. Over the course of ~9 yr of H.E.S.S observations the VHE light curve in the quiescent state is consistent with a log-normal behavior. The VHE variability in this state is well described by flicker noise (power-spectral-density index {\ss}_VHE = 1.10 +0.10 -0.13) on time scales larger than one day. An analysis of 5.5 yr of HE Fermi LAT data gives consistent results ({\ss}_HE = 1.20 +0.21 -0.23, on time scales larger than 10 days) compatible with the VHE findings. The HE and VHE power spectral densities show a scale invariance across the probed time ranges. A direct linear correlation between the VHE and HE fluxes could neither be excluded nor firmly established. These long-term-variability properties are discussed and compared to the red noise behavior ({\ss} ~ 2) seen on shorter time scales during VHE-flaring states. The difference in power spectral noise behavior at VHE energies during quiescent and flaring states provides evidence that these states are influenced by different physical processes, while the compatibility of the HE and VHE long-term results is suggestive of a common physical link as it might be introduced by an underlying jet-disk connection.Comment: 11 pages, 16 figure

Novel PI3Kγ Mutation in a 44-Year-Old Man with Chronic Infections and Chronic Pelvic Pain

A 44-year-old man is presented here with 14 years of chronic purulent sinusitis, a chronic fungal rash of the scrotum, and chronic pelvic pain. Treatment with antifungal therapy resulted in symptom improvement, however he was unable to establish an effective long-term treatment regimen, resulting in debilitating symptoms. He had undergone extensive work-up without identifying a clear underlying etiology, although Candida species were cultured from the prostatic fluid. 100 genes involved in the cellular immune response were sequenced and a missense mutation was identified in the Ras-binding domain of PI3Kγ. PI3Kγ is a crucial signaling element in leukotaxis and other leukocyte functions. We hypothesize that his mutation led to his chronic infections and pelvic pain