Narrow Results

Globular clusters are gravitationally bound stellar systems containing on the order of 10⁵ stars. Due to the high stellar densities in the cores of these clusters, close encounters and even physical collisions between stars are inevitable. These dynamical interactions can produce exotic types of single and binary stars that are extremely rare in the galactic field, but which may be important to the dynamical evolution of their host clusters. A common feature of these dynamically-formed stellar populations is that many of their members are relatively hot, and thus bright in the far-ultraviolet (FUV) waveband. In this short review, we describe how space-based FUV observations are being used to find and study these populations.

The binary system AR Scorpii hosts an M-type main sequence cool star orbiting around a magnetic white dwarf in the Milky Way Galaxy. The broadband non-thermal emission over radio, optical and X-ray wavebands observed from AR Scorpii indicates strong modulations on the spin frequency of the white dwarf as well as the spin-orbit beat frequency of the system. Therefore, AR Scorpii is also referred to as a white dwarf pulsar wherein a fast spinning white dwarf star plays very crucial role in the broadband non-thermal emission. Several interpretations for the observed features of AR Scorpii appear in the literature without firm conclusions. In this paper, we investigate connection between some of the important physical properties like spin-down power, surface magnetic field, equation of state, temperature and gravity associated with the white dwarf in the binary system AR Scorpii and its observational characteristics. We explore the plausible effects of white dwarf surface magnetic field on the absence of substantial accretion in this binary system and also discuss the gravitational wave emission due to magnetic deformation mechanism.

In this paper, we have collected the available observation data of BL Lac S5 0716+714 in I-band from published literature during 1994 to 2000. The light curve shows S5 0716+714 is very active and very complicated non-sinusoidal variations. We studied its medium-timescale periodicity using the Jurkevich and power spectrum method to search for the possible medium-timescale periods and found that one possible medium-timescale periodic with a period of around 14±0.1 day is obtained for S5 0716+714. It is interesting to note that these results are in good agreement with the previous results by Impey et al. (2000) and Qian et al. (2002), and this work provides a new analysis and evidence of the medium-timescale periodicity in BL Lac S5 0716+714. The helical jet model seems to be more reasonable for explaining our results than other models.

This study aims to explore the dynamic capabilities (DCs) framework (with sensing, seizing, and reconfiguration dimensions) by exploring the fulfilment layer and underlying processes and structures employed in business model innovation (BMI) process within both new and established entrepreneurial firms. We employed exploratory and descriptive qualitative research method and gathered data through semi-structured interviews with entrepreneurs of nine firms operating in the science-park settings in Istanbul, Türkiye. This study uncovered rich insights about the DCs, as categorized in this study under 10 sub-dimensions. In addition, three different fulfilment layers of DCs emerged at the entrepreneurial firms: (i) the entrepreneurial capabilities at the individual layer, (ii) the entrepreneurial team’s complementary capabilities at the top managerial layer, and (iii) the mechanisms and routines at the organizational layer. DC sub-dimensions suggested in our study are clues for entrepreneurs to develop BMIs. Practitioners are recommended to consider their primary responsibility for BMIs processes independent of the size of the firms, to build entrepreneurial teams with partners having the complementary skill set and concentrate on the employees’ selection, as well as their adaptation to the firm routines. Additionally, the study complements Teece’s theoretical DC framework on BMI extending it into fulfilment layer and opens a fruitful research area for scholars.

This paper explores orchestration capability as a concept defining the firm's ability to purposefully build and manage innovation networks. Due to the lack of empirical research on the subject as well as the focus on the organizational level in earlier studies, we approach the issue from a multi-level perspective. By utilizing expert panel discussions and an in-depth case study in an innovation network, we show that orchestration capability consists of both organizational and individual level determinants. Distinct capabilities and skills are identified and illustrated. Furthermore, we identify mechanisms suggesting that the two levels are interconnected in several ways.

Absorptive capacity (AC) describes new knowledge absorption and its use for innovation on an organisational level. In this paper, we explore the role of individual AC (IAC) for corporate innovation. We focus on the individual and relationships among the capability dimensions of existing AC models. A quantitative online survey allows us to empirically explore and underline the role of the individual in AC. Our findings contribute to and extend existing theories of AC, by confirming the multidimensionality of IAC, shed light on the view of transformation and exploitation as alternative paths and their effect on different innovation processes. Our research highlights the individual’s central role in innovation and introduces, explores and evaluates individual capacities to absorb new knowledge. This in consequence will influence processes and structures within a company with regard to innovation and human resource management.

The South Pole Telescope (SPT) is a 10-meter telescope designed to survey the millimeter-wave sky, taking advantage of the exceptional observing conditions at the Amundsen-Scott South Pole Station. The telescope and its ground-breaking 960-element bolometric camera finished surveying 2500 square degrees at 95. 150, and 220 GHz in November 2011. We have discovered hundreds of galaxy clusters in the SPT-SZ survey through the Sunyaev-Zel’dovich (SZ) effect. The formation of galaxy clusters the largest bound objects in the universe is highly sensitive to dark energy and the history of structure formation. I will discuss the cosmological constraints from the SPT-SZ galaxy cluster sample as well as future prospects with the soon to-be-installed SPT-3G camera.

Absorptive capacity (AC) describes new knowledge absorption and its use for innovation on an organisational level. In this paper, we explore the role of individual AC (IAC) for corporate innovation. We focus on the individual and relationships among the capability dimensions of existing AC models. A quantitative online survey allows us to empirically explore and underline the role of the individual in AC. Our findings contribute to and extend existing theories of AC, by confirming the multidimensionality of IAC, shed light on the view of transformation and exploitation as alternative paths and their effect on different innovation processes. Our research highlights the individual’s central role in innovation and introduces, explores and evaluates individual capacities to absorb new knowledge. This in consequence will influence processes and structures within a company with regard to innovation and human resource management.

The recent associations of neutrino events with blazars (e.g. TXS 0506+056, 3HSP J095507.9+355101) provided a unique opportunity to study the possible physical connection between the multiwavelength electromagnetic and neutrino emissions. We present SOPRANO, a new conservative implicit kinetic code which follows the time evolution of the isotropic distribution functions of protons, neutrons and the secondaries produced in photo-pion and photo-pair interactions, alongside with the evolution of photon and electron/positron distribution functions. In the current work, we apply SOPRANO to model the broadband spectrum of TXS 0506+056, 3HSP J095507.9+355101 and 3C 279 blazars. It was possible to constrain main physical parameters within both a pure hadronic and lepto-hadronic scenarios.

Low-luminosity gamma-ray bursts (GRBs) have small isotropic equivalent gamma-ray energy and luminosity, compared with normal long GRBs. GRB 190829A is a member of this class. Furthermore, very-high-energy gamma-rays were detected by H.E.S.S. with ∼ 20σ significance. This event had more unusual features. First, it had much smaller isotropic equivalent gamma-ray energy than typical long gamma-ray bursts and is classified as low-luminosity GRB. Second, early X-ray and optical afterglow emission showed a rising part and simultaneously peaked at about 1400 s. We propose an off-axis jet scenario that explains these observational results. In this model, the relativistic beaming effect is responsible for the apparently small isotropic gamma-ray energy and spectral peak energy. Using a jetted afterglow model, we find that the narrow jet, which has the initial Lorentz factor of 350 and the initial jet opening half-angle of 0.015 rad, viewed off-axis can describe the observed achromatic behavior in the X-ray and optical afterglow. Another wide, baryon-loaded jet is necessary for the later-epoch X-ray and radio emissions. Derived parameters explains the very-high-energy gamma-ray flux at 20,000 s.

We report on the results of two successful, simultaneous observations of Sagittarius A* at the center of the Milky Way. The observations were carried out in 2004 and 2008 using telescopes operating from the mm-radio domain to the X-ray domain, and detected strong flux density variations in all wavelength bands. Modeling suggests that a combination of a synchrotron self Compton process and an adiabatic expansion of source components are at work. The luminous flare emission of Sagittarius A* also supports the presence of an accreting super massive black hole at that position. We also discuss the potential of NIR interferometry for further detailed investigations of the accretion process in SgrA*.

We show that exoplanets in the M31 galaxy may be detected with the pixel-lensing method by using telescopes making high cadence observations of an ongoing microlensing event. Although the mean mass for detectable exoplanets is about 2 M_J, even small mass exoplanets (M_P < 20 M_⊕) can cause significant deviations, which are observable with large telescopes. We reanalysed the POINT-AGAPE microlensing event PA-99-N2. First, we test the robustness of the binary lens conclusion for this light curve. Second, we show that for such long duration and bright microlensing events, the efficiency for finding planetary-like deviations is strongly enhanced.

As suggested by optical observations, the globular cluster NGC 6388 may harbor a central intermediate-mass black hole with mass of about 5.7 × 10³ M_⊙. We review the past X-ray and radio observations conducted towards NGC 6388 with particular attention to IGRJ17361-4441, i.e. a high energy transient recently discovered by using the INTEGRAL satellite. The transient was located at the globular cluster center thus leaving the intriguing possibility that it may be associated to the central black hole activity.