RESUMO
We present new constraints on the dark matter-induced annual modulation signal using 1.7 years of COSINE-100 data with a total exposure of 97.7 kg yr. The COSINE-100 experiment, consisting of 106 kg of NaI(Tl) target material, is designed to carry out a model-independent test of DAMA/LIBRA's claim of WIMP discovery by searching for the same annual modulation signal using the same NaI(Tl) target. The crystal data show a 2.7 cpd/kg/keV background rate on average in the 2-6 keV energy region of interest. Using a χ-squared minimization method we observe best fit values for modulation amplitude and phase of 0.0092±0.0067 cpd/kg/keV and 127.2±45.9 d, respectively.
RESUMO
A search for inelastic boosted dark matter (IBDM) using the COSINE-100 detector with 59.5 days of data is presented. This relativistic dark matter is theorized to interact with the target material through inelastic scattering with electrons, creating a heavier state that subsequently produces standard model particles, such as an electron-positron pair. In this study, we search for this electron-positron pair in coincidence with the initially scattered electron as a signature for an IBDM interaction. No excess over the predicted background event rate is observed. Therefore, we present limits on IBDM interactions under various hypotheses, one of which allows us to explore an area of the dark photon parameter space that has not yet been covered by other experiments. This is the first experimental search for IBDM using a terrestrial detector.
RESUMO
TSH-secreting adenomas are rare tumors, representing only 0.5 to 2.5% of pituitary adenomas. Their main clinical characteristics include signs of thyrotoxicosis, diffuse goiter and a compressive syndrome. Biologically, free T4 and T3 serum levels are elevated, contrasting with inadequate serum TSH levels and increased alpha chains. Magnetic resonance (MR) imaging shows a pituitary tumor, the main differential diagnosis being resistance to thyroid hormones. Treatment is based on surgery, possibly associated with somatostatin analogs and radiotherapy. Though the long-term evolution of this rare pathology seems to have improved, some clinical situations are still a challenge to treat. We report one such case that was resistant to both stereotactic radiotherapy and somatostatin analogs, but surprisingly improved with cabergoline. We suggest that cabergoline should be considered as an alternative treatment in cases of pituitary adenomas that resist traditional treatments.
Assuntos
Antineoplásicos/uso terapêutico , Ergolinas/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/metabolismo , Tireotropina/metabolismo , Adulto , Osso e Ossos/anormalidades , Osso e Ossos/patologia , Cabergolina , Humanos , Masculino , Neoplasias Hipofisárias/sangue , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangueRESUMO
The COSINE-100 dark matter search experiment is an array of NaI(Tl) crystal detectors located in the Yangyang Underground Laboratory (Y2L). To understand measured backgrounds in the NaI(Tl) crystals we have performed Monte Carlo simulations using the Geant4 toolkit and developed background models for each crystal that consider contributions from both internal and external sources, including cosmogenic nuclides. The background models are based on comparisons of measurement data with Monte Carlo simulations that are guided by a campaign of material assays and are used to evaluate backgrounds and identify their sources. The average background level for the six crystals (70 kg total mass) that are studied is 3.5 counts/day/keV/kg in the (2-6) keV energy interval. The dominant contributors in this energy region are found to be 210 Pb and 3 H.