167 research outputs found

    Constraints on Modified Gravity from ACT and SPT

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    The Atacama Cosmology Telescope (ACT) and the South Pole Telescope (SPT) have recently provided new and precise measurements of the Cosmic Microwave Background anisotropy damping tail. This region of the CMB angular spectra, thanks to the angular distortions produced by gravitational lensing, can probe the growth of matter perturbations and provide a test for general relativity. Here we make use of the ACT and SPT power spectrum measurements (combined with the recent WMAP9 data) to constrain f(R) gravity theories. Adopting a parametrized approach, we obtain an upper limit on the lengthscale of the theory of B_0 < 0.86 at 95% c.l. from ACT, while we get a significantly stronger bound from SPT with B_0 < 0.14 at 95% c.l..Comment: 6 pages, 4 figures, some sentences correcte

    Photometric Analysis and Rotation Period Determination for Asteroids 5445 Williwaw, (8823) 1987 WS3 and (26568) 2000 ET49

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    Photometric observations of three main-belt asteroids were conducted in order to determine their synodic rotation periods. For 5445 Williwaw we found P = 10.65 ± 0.02 h, A = 0.29 ± 0.05 mag; for (8823) 1987 WS3, a slow rotator, we found a rough period of P = 86.0 ± 1.0 h, A = 0.24 ± 0.02 mag; for (26568) 2000 ET49 we found P = 7.171 ± 0.003 h, A = 0.71 ± 0.04 ma

    Blue Gravity Waves from BICEP2 ?

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    We present new constraints on the spectral index n_T of tensor fluctuations from the recent data obtained by the BICEP2 experiment. We found that the BICEP2 data alone slightly prefers a positive, "blue", spectral index with n_T=1.36\pm0.83 at 68 % c.l.. However, when a TT prior on the tensor amplitude coming from temperature anisotropy measurements is assumed we get n_T=1.67\pm0.53 at 68 % c.l., ruling out a scale invariant nT=0n_T=0 spectrum at more than three standard deviations. These results are at odds with current bounds on the tensor spectral index coming from pulsar timing, Big Bang Nucleosynthesis, and direct measurements from the LIGO experiment. Considering only the possibility of a "red", n_T<0 spectral index we obtain the lower limit n_T > -0.76 at 68 % c.l. (n_T>-0.09 when a TT prior is included).Comment: 3 Pages, 4 Figure

    Changes in biological properties and antioxidant capacity of an agricultural soil amended with sewage sludge

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    The effects of applying sewage sludge (SS) to agricultural soil (at low rate of 22.5, LRS, and at high rate of 45 t ha−1 dry basis, HRS) were monitored over a 120-d experimental period. Total organic carbon (TOC), water- soluble organic carbon (WSOC), alkali-soluble phenols, basal respiration, 10 specific enzyme activity, dehydrogenase activity (DH-ase), metabolic potential (MP) and FDA-hydrolytic activity (FDA) were strongly increased by both rates of SS applications. In the SS amended soil, about 70% of the organic C added with the material remained at the end of the experiment. Basal respiration increased with increasing SS doses. The 15 specific enzyme activity and the MP indicate an increase in the enzyme activity in soil. AQ10 The addition of SS led to higher values than the control of all the tested parameters up to the end of the experimental period. The anti- oxidant capacity (trolox equivalent antioxidant capacity, TEAC) was influ- 20 enced by SS addition only when applied at HRS. After 120 days only HRS value of TEAC (5.13 mM g−1) was higher than control (4.09 mM g−1). The pattern of TEAC did not enable any link to be established between antioxidant capacity and both alkali-soluble phenols and basal respira- tion in soil

    Spin axis and shape model for 1117 Reginita

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    We present shape and spin axis model for main-belt asteroid 1117 Reginita. The model was achieved with the lightcurve inversion process using combined dense photometric data acquired from nine apparitions between 2003-2018 and sparse data from USNO Flagstaff. Analysis of the resulting data found a sidereal period P = 2.946472 ± 0.000002 hours and two mirrored pole solutions at (λ = 0°, β = 43°) and (λ = 174°, β = 47°) with an uncertainty of ± 5 degrees.peer-reviewe

    357 Ninina and 748 Simeisa - Two Asteroids with Earth Commensurate Rotation Periods

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    A global collaboration of observers from Australia, Europe, and North America found synodic rotation periods and amplitudes for 357 Ninina 35.983 ± 0.001 h, 0.11 ± 0.01 magnitudes; 748 Simeisa 11.903 ± 0.001 h, 0.08 ± 0.01 magnitudes

    Characterization and origin of organic and inorganic pollution in urban soils in Pisa (Tuscany, Italy).

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    We assessed the quality of 31 urban soils in Pisa by analyzing total petroleum hydrocarbons (TPH), Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn and the platinum group (PGEs). The risk was evaluated by the geological accumulation index (Igeo) and the enrichment factor (EF). Results were compared with those obtained from a non-urban site and with the quantitative limits fixed by Italian legislation. In nearly all the monitored sites, the legal limit for TPH of 60 mg/kg in residential areas was exceeded, indicating widespread and intense pollution throughout the entire city area. The Igeo indicated no Cd, Cu, Mn, Ni and Zn pollution and minimal Pb and Cr pollution, due to anthropogenic enrichment. Legal Hg and Zn limits of 1 and 150 mg/kg respectively were exceeded in about 20% of sites, Cd (2 mg/kg), Cr (150 mg/kg) and Cu (120 mg/kg) in only one site, the Ni legal limit of 120 mg/kg was never exceeded. Some urban soils showed a higher Hg level than the more restrictive legal limit of 5 mg/kg concerning areas for industrial use. Based on the soluble, exchangeable and carbonate-bound fractions, Mn and Zn showed the highest mobility, suggesting a more potential risk of soil contamination than the other metals. The TPH and both Cr and Hg amounts were not correlated with any of the other monitored metals. The total contents of Cd, Pb, Zn and Cu in soils were positively correlated with each other, suggesting a common origin from vehicular traffic. The PGE values (Pt and Pd) were below the detection limits in 75% - 90% of the monitored areas, suggesting that their accumulation is at an early stage

    Analisi del periodo di AE UMa con dati disomogenei. Invito all'osservazione.

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    L’idea di questo lavoro è nata dalla volontà di analizzare i dati di AE UMa, raccolti indipendentemente dagli autori, frutto di osservazioni filtrate e non, ottenute con una diversa strumentazione ed in condizioni operative diverse. Più in generale si è cercato di verificare la possibilità di utilizzare delle osservazioni non omogenee tra loro per lo studio dell’analisi del periodo, confrontandone i risultati con quelli pubblicati in letteratura.The idea for this study was born from a desire to analyze AE UMa data collected independently by the authors, which were the result of filtered and non filtered observations, obtained with different instruments and under different operating conditions. More generally, we attempted to explore the possibility of using non-homogeneous observations to study the period, by comparing our results with those published in the literature

    Rotation period determination for 3157 Novikov and 7485 Changchun

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    Collaborative photometric observations of two main-belt asteroids were conducted from five observatories in order to determine their synodic rotation periods. For 3157 Novikov we found a period of 9.952 ± 0.001 h with an amplitude of 0.31 ± 0.04 mag, for 7485 Changchun we found a period of 10.234 ± 0.001 h with an amplitude of 0.39 ± 0.02 mag.peer-reviewe
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