The blue sky of GJ3470b: the atmosphere of a low-mass planet unveiled by ground-based photometry

GJ3470b is a rare example of a "hot Uranus" transiting exoplanet orbiting a nearby M1.5 dwarf. It is of crucial interest for atmospheric studies because it is one of the most inflated low-mass planets known, bridging the boundary between "super-Earths" and Neptunian planets. We present two new ground-based light curves of GJ3470b gathered by the LBC camera at the Large Binocular Telescope. Simultaneous photometry in the ultraviolet (lambda_c = 357.5 nm) and optical infrared (lambda_c = 963.5 nm) allowed us to detect a significant change of the effective radius of GJ3470b as a function of wavelength. This can be interpreted as a signature of scattering processes occurring in the planetary atmosphere, which should be cloud-free and with a low mean molecular weight. The unprecedented accuracy of our measurements demonstrates that the photometric detection of Earth-sized planets around M dwarfs is achievable using 8-10m size ground-based telescopes. We provide updated planetary parameters, and a greatly improved orbital ephemeris for any forthcoming study of this planet.Comment: 8 pages, 6 figures, 1 table; accepted for publication in A&

A novel combinatorial technique for simultaneous quantification of oxygen radicals and aggregation reveals unexpected redox patterns in the activation of platelets by different physiopathological stimuli

This is the author accepted manuscript. The final version is available fromFerrata Storti Foundation via the DOI in this recordThe regulation of platelets by oxidants is critical for vascular health and may explain thrombotic complications in diseases such as diabetes and dementia, but remains poorly understood. Here, we describe a novel technique combining electron paramagnetic resonance spectroscopy and turbidimetry, which has been utilised to monitor simultaneously platelet activation and oxygen radical generation. This technique has been used to investigate the redox-dependence of human and mouse platelets. Using selective peptide inhibitors of NOXs on human platelets and genetically modified mouse platelets (NOX1-/- or NOX2-/-), we discovered that:1) intracellular but not extracellular superoxide anion generated by NADPH oxidases (NOXs) is critical for platelet activation by collagen; 2) superoxide dismutation to hydrogen peroxide is required for thrombin-dependent activation; 3) NOX1 is the main source of oxygen radicals in response to collagen, while NOX2 is critical for activation by thrombin; 4) two platelet modulators, namely oxidised low density lipoproteins (oxLDL) and amyloid peptide β (Aβ), require activation of both NOX1 and NOX2 to pre-activate platelets. This study provides new insights on the redox dependence of platelet activation. It suggests the possibility of selectively inhibiting platelet agonists by targeting either NOX1 (for collagen) or NOX2 (for thrombin). Selective inhibition of either NOX1 or NOX2 impairs the potentiatory effect of tested platelet modulators (oxLDL and Aβ), but does not completely abolish platelet haemostatic function. This information offers new opportunities for the development of disease specific antiplatelet drugs with limited bleeding side effects by selectively targeting one NOX isoenzyme.British Heart Foundatio

A strongly interacting gas of two-electron fermions at an orbital Feshbach resonance

We report on the experimental observation of a strongly interacting gas of ultracold two-electron fermions with orbital degree of freedom and magnetically tunable interactions. This realization has been enabled by the demonstration of a novel kind of Feshbach resonance occurring in the scattering of two 173Yb atoms in different nuclear and electronic states. The strongly interacting regime at resonance is evidenced by the observation of anisotropic hydrodynamic expansion of the two-orbital Fermi gas. These results pave the way towards the realization of new quantum states of matter with strongly correlated fermions with orbital degree of freedom.Comment: 5 pages, 4 figure

Large Binocular Telescope view of the atmosphere of GJ1214b

The atmospheric composition and vertical structure of the super-Earth GJ1214b has been a subject of debate since its discovery in 2009. Recent studies have indicated that high-altitude clouds might mask the lower layers. However, some data points that were gathered at different times and facilities do not fit this picture, probably because of a combination of stellar activity and systematic errors. We observed two transits of GJ1214b with the Large Binocular Camera, the dual-channel camera at the Large Binocular Telescope. For the first time, we simultaneously measured the relative planetary radius $k=R_\mathrm{p}/R_\star$ at blue and red optical wavelengths ($B+R$), thus constraining the Rayleigh scattering on GJ1214b after correcting for stellar activity effects. To the same purpose, a long-term photometric follow-up of the host star was carried out with WiFSIP at STELLA, revealing a rotational period that is significantly longer than previously reported. Our new unbiased estimates of $k$ yield a flat transmission spectrum extending to shorter wavelengths, thus confirming the cloudy atmosphere scenario for GJ1214b.Comment: 11 pages, 5 figures, 3 tables. Published in A&A. Minor changes to reflect the published versio

Markov Chain Beam Randomization: a study of the impact of PLANCK beam measurement errors on cosmological parameter estimation

We introduce a new method to propagate uncertainties in the beam shapes used to measure the cosmic microwave background to cosmological parameters determined from those measurements. The method, which we call Markov Chain Beam Randomization, MCBR, randomly samples from a set of templates or functions that describe the beam uncertainties. The method is much faster than direct numerical integration over systematic `nuisance' parameters, and is not restricted to simple, idealized cases as is analytic marginalization. It does not assume the data are normally distributed, and does not require Gaussian priors on the specific systematic uncertainties. We show that MCBR properly accounts for and provides the marginalized errors of the parameters. The method can be generalized and used to propagate any systematic uncertainties for which a set of templates is available. We apply the method to the Planck satellite, and consider future experiments. Beam measurement errors should have a small effect on cosmological parameters as long as the beam fitting is performed after removal of 1/f noise.Comment: 17 pages, 23 figures, revised version with improved explanation of the MCBR and overall wording. Accepted for publication in Astronomy and Astrophysics (to appear in the Planck pre-launch special issue

A novel CMB polarization likelihood package for large angular scales built from combined WMAP and Planck LFI legacy maps

We present a CMB large-scale polarization dataset obtained by combining WMAP Ka, Q and V with Planck 70 GHz maps. We employ the legacy frequency maps released by the WMAP and Planck collaborations and perform our own Galactic foreground mitigation technique, which relies on Planck 353 GHz for polarized dust and on Planck 30 GHz and WMAP K for polarized synchrotron. We derive a single, optimally-noise-weighted, low-residual-foreground map and the accompanying noise covariance matrix. These are shown, through $\chi^2$ analysis, to be robust over an ample collection of Galactic masks. We use this dataset, along with the Planck legacy Commander temperature solution, to build a pixel-based low-resolution CMB likelihood package, whose robustness we test extensively with the aid of simulations, finding excellent consistency. Using this likelihood package alone, we constrain the optical depth to reionazation $\tau=0.069^{+0.011}_{-0.012}$ at $68\%$ C.L., on 54\% of the sky. Adding the Planck high-$\ell$ temperature and polarization legacy likelihood, the Planck lensing likelihood and BAO observations we find $\tau=0.0714_{-0.0096}^{+0.0087}$ in a full $\Lambda$CDM exploration. The latter bounds are slightly less constraining than those obtained employing \Planck\ HFI CMB data for large angle polarization, that only include EE correlations. Our bounds are based on a largely independent dataset that does include also TE correlations. They are generally well compatible with Planck HFI preferring slightly higher values of $\tau$. We make the low-resolution Planck and WMAP joint dataset publicly available along with the accompanying likelihood code.Comment: The WMAP+LFI likelihood module is available on \http://www.fe.infn.it/u/pagano/low_ell_datasets/wmap_lfi_legacy

Synergies between space telescopes in the photometric characterization of the atmospheres of Hot Jupiters

Previous generation of instruments have the opportunity to discover thousands of extra-solar planets and more will come with the current and future planet-search missions. In order to go one step further in the characterization of exoplanets, in this paper we describe a way to compare the photometric observation of Hot Jupiters done with space telescopes such as HST, CHEOPS, TESS, PLATO, and JWST and give the first-hand characterization on their atmospheres. We analyze a set of planetary systems hosting a Hot Jupiter for which an atmospheric template is available in the literature. For each system, we simulate the transit light curves observed by different instruments, convolving the incoming spectrum with the corresponding instrumental throughput. For each instrument, we thus measure the expected transit depth and estimate the associated uncertainty. Finally, we compare the transit depths as seen by the selected instruments and we quantify the effect of the planetary atmosphere on multi-band transit photometry. We also analyze a set of simulated scenarios with different stellar magnitudes, activity levels, transit durations and atmospheric templates to find the best cases for this kind of observational approach. We find in general that current and especially future space telescopes provide enough photometric precision to detect significant differences between the transit depths at different wavelengths. In particular, we find that the chromatic effect due to the atmosphere of the Hot Jupiters is maximized at later spectral types and that the effect of stellar activity is smaller than the measurement uncertainties.Comment: 14 pages, 17 figures, Published in MNRA

Strategies for Agile Leadership in a Challenging Environment

The post pandemic environment has provided many significant challenges for all forms of organisations. The requirement for good leadership in this context is vital. This research considers the features of such leadership and how their application can affect organisations and their required outputs. The need for agility in this sphere is proposed, in order to accommodate the environmental challenges, globally and within the different sectors. There should be an emphasis on creativity in order to provide solutions to the many issues for organisations in the prevailing environment. Recruitment and retention are viewed as critical activities for sustaining these entities by ensuring the supply of the requisite standard of personnel at all levels. The latter should have suitable qualifications or the aptitude to acquire them. These staff should be given appropriate training then empowered, including being given the scope to utilise their own leadership style, as appropriate. The form of the post pandemic environment and its effects on leadership are noted. The principal factors identified here include the economic challenges, hybrid working patterns and the use of agency staff to supplement the permanent resource. The proactive development of leaders is emphasised as a critical activity for organisations, enabling them to address the issues prevalent in their environment. Research into this area occurred, using qualitative techniques. A literature review and interview with a current practitioner were performed, in order to glean the data for an inductive analysis. A template to assist organisations in creating a strategy for ‘Agile Leadership’ was then formulated.How to cite this article: Blair, G., Barratt, S., & Pagano, R., (2023). Strategies for Agile Leadership in a Challenging Environment. GS Spark: Journal of Applied Academic Discourse. 1(1), 55-66. https://doi.org/10.5281/zenodo.837211

Electrical tomography and TDEM prospection in the Chianciano thermal basin (Siena, Italy)

Chianciano thermal basin in Tuscany belongs to a great structure that extends, from San Casciano Bagni to Rapolano, orientated SSE-NNW. Several springs are located in this thermal field: Acqua Santa, Macerina, Casuccini and Sillene well. They are located close to the contact between the lower complex of the «Tuscan series» (Triassic limestones and dolomites) and Pliocene formations (sands and clayey sands, clays and silty clays). According to the groundwater flow scheme, the former formations represent the geothermal reservoir and, where they outcrop, the recharge areas. Thermalized fluids rise through direct faults, having an apennine orientation. In order to locate a new production well, electrical tomography and TDEM prospection were performed. Geophysical interpretation led to the construction of 1D imaged and 2D sections showing the main tectonic features. The different electrical behaviour of the hydrogeological units disclosed a fault located near the old Sillene well; this tectonic feature caused the uplifting of Triassic formations towards the north-east. A new production well was located close to the fault in the uplifted sector with excellent results as it captured the thermal aquifer at a depth of 30 m with a discharge up to 70 l/s