Ratios of Fluctuation Observables in the Search for the QCD Critical Point

The QCD critical point can be found in heavy ion collision experiments via the non-monotonic behavior of many fluctuation observables as a function of the collision energy. The event-by-event fluctuations of various particle multiplicities are enhanced in those collisions that freeze out near the critical point. Higher, non-Gaussian, moments of the event-by-event distributions of such observables are particularly sensitive to critical fluctuations, since their magnitude depends on the critical correlation length to a high power. We present quantitative estimates of the contribution of critical fluctuations to the third and fourth moments of the pion and proton, as well as estimates of various measures of pion-proton correlations, all as a function of the same five non-universal parameters. We show how to use nontrivial but parameter independent ratios among these more than a dozen fluctuation observables to discover the critical point. We also construct ratios that, if the critical point is found, can be used to overconstrain the values of the non-universal parameters.Comment: 5 pages, 1 figure - Talk given by C. Athanasiou at Hot Quarks 201

Radiation of a circulating quark in strongly coupled N=4 super Yang-Mills theory

The energy density and angular distribution of power radiated by a quark undergoing circular motion in strongly coupled ${\cal N}=4$ supersymmetric Yang-Mills (SYM) theory is computed using gauge/gravity duality. The results are qualitatively similar to that of synchrotron radiation produced by an electron in circular motion in classical electrodynamics: At large velocities the quark emits radiation in a narrow beam along its velocity vector with a characteristic opening angle $\alpha \sim 1/\gamma$ and radial thickness scaling like $\sim 1/\gamma^3$.Comment: 8 pages, 2 figures - Talk presented by D. Nickel at QCD@Work, June 20-23rd, 2010, Martina Franca, Ital

Synchrotron radiation in strongly coupled conformal field theories

Using gauge/gravity duality, we compute the energy density and angular distribution of the power radiated by a quark undergoing circular motion in strongly coupled ${\cal N}=4$ supersymmetric Yang-Mills (SYM) theory. We compare the strong coupling results to those at weak coupling, and find the same angular distribution of radiated power, up to an overall prefactor. In both regimes, the angular distribution is in fact similar to that of synchrotron radiation produced by an electron in circular motion in classical electrodynamics: the quark emits radiation in a narrow beam along its velocity vector with a characteristic opening angle $\alpha \sim 1/\gamma$. To an observer far away from the quark, the emitted radiation appears as a short periodic burst, just like the light from a lighthouse does to a ship at sea. Our strong coupling results are valid for any strongly coupled conformal field theory with a dual classical gravity description.Comment: 20 pages, 8 figures. v2: published version. v4: factor-of-two error corrected in the time-averaged angular distribution of the power radiated in scalars in weak coupling N=4 SYM theory; correcting this error has interesting ramification

Probing Supersymmetry With Third-Generation Cascade Decays

The chiral structure of supersymmetric particle couplings involving third generation Standard Model fermions depends on left-right squark and slepton mixings as well as gaugino-higgsino mixings. The shapes and intercorrelations of invariant mass distributions of a first or second generation lepton with bottoms and taus arising from adjacent branches of SUSY cascade decays are shown to be a sensitive probe of this chiral structure. All possible cascade decays that can give rise to such correlations within the MSSM are considered. For bottom-lepton correlations the distinctive structure of the invariant mass distributions distinguishes between decays originating from stop or sbottom squarks through either an intermediate chargino or neutralino. For decay through a chargino the spins of the stop and chargino are established by the form of the distribution. When the bottom charge is signed through soft muon tagging, the structure of the same-sign and opposite-sign invariant mass distributions depends on a set function of left-right and gaugino-higgsino mixings, as well as establishes the spins of all the superpartners in the sequential two-body cascade decay. Tau-lepton and tau-tau invariant mass distributions arising from MSSM cascade decays are likewise systematically considered with particular attention to their dependence on tau polarization. All possible tau-lepton and tau-tau distributions are plotted using a semi-analytic model for hadronic one-prong taus. Algorithms for fitting tau-tau and tau-lepton distributions to data are suggested.Comment: 35 pages, 17 .eps figure

An Anxiety Epidemic in the Financialized University: Critical questions and Unexpected Resistance

Financialization is transforming social subjects and institutions, including the university. This article explores overlooked links between the financialization of public postsecondary education on both sides of the North Atlantic and the ongoing “anxiety epidemic” among students (and, indeed, staff). The article argues that the “anxious university” represents a unique space to study the economic, political, social, and cultural impact of the rise in power and influence of the financial sector. By unraveling the complex sociological dimensions of the anxiety epidemic, we offer a vantage on the emergence of new forms an

Strongly-Coupled Quarks and Colorful Black Holes

We use the AdS/CFT correspondence to study the behavior of strongly-coupled quarks in a black hole background. The supergravity background consists of a six-dimensional Schwarzschild-black string AdS soliton, for which the bulk horizon extends from the AdS boundary down to an infra-red floor. By going to higher energy scales, the regime of validity of the classical supergravity background can be extended closer to the singularity than might be expected from the four-dimensional perspective. Small black holes potentially created by the Large Hadron Collider could typically carry color charges inherited from their parton progenitors. The dynamics of quarks near such a black hole depends on the curved spacetime geometry as well as the strong interaction with the color-charged black hole. We study the resulting behavior of quarks and compute the rate at which a quark rotating around the black hole loses energy. We also investigate how the interaction between a quark and an antiquark is altered by the presence of the black hole, which results in a screening length.Comment: Proceedings of the DPF-2011 Conference, 8 pages, 5 figures, added reference

The laboratory diagnostic approach to thoracic and abdominal effusions in the dog, cat, and horse

Περιστατικά στα οποία διαπιστώνονται υπεζωκοτικές και περιτοναϊκές συλλογές είναι αρκετά συχνά στην κλινική πράξη. Ο καθορισμός της υποκείμενης αιτιολογίας σε αυτές τις περιπτώσεις βασίζεται κυρίως στην ανάλυση του υγρού της συλλογής. Η τεχνική που χρησιμοποιείται για τη λήψη του υγρού της υπεζωκοτικής ή περιτοναϊκής συλλογής μπορεί να επηρεάσει σε μεγάλο βαθμό τα αποτελέσματα της ανάλυσης. Στις πιο συχνά χρησιμοποιούμενες διαγνωστικές εξετάσεις περιλαμβάνονται η αξιολόγηση των φυσικών ιδιοτήτων του υγρού, ο προσδιορισμός του συνολικού αριθμού εμπύρηνων κυττάρων / ολικών πρωτεϊνών (TNCC / TP), ο προσδιορισμός χημικών / βιοχημικών παραμέτρων (γαλακτική αφυδρογονάση και γαλακτικό οξύ, χολοστερόλη, τριγλυκερίδια, γλυκόζη, κρεατινίνη, pH, pO2, pCO2, K), κυτταρολογική εξέταση (διάγνωση σηπτικών και μη σηπτικών φλεγμονών και νεοπλασμάτων), μικροβιολογικές εξετάσεις (επιχρίσματα με χρώση Gram, καλλιέργεια, μοριακές τεχνικές) και ειδικές διαγνωστικές εξετάσεις για ορισμένες παθολογικές καταστάσεις και νοσήματα. Η ταξινόμηση μιας συλλογής ως διίδρωμα, τροποποιημένο διίδρωμα και εξίδρωμα βασίζεται παραδοσιακά στις τιμές των TNCC και ΤΡ. Νέες διαγνωστικές μέθοδοι συνεισφέρουν στην αιτιολογική διάγνωση χωρίς απαραίτητα να ακολουθηθεί αυστηρά η παραδοσιακή ταξινόμηση. Πολλές από τις διαγνωστικές εξετάσεις που περιγράφονται σε αυτήν την ανασκόπηση είναι απλές και μπορούν να πραγματοποιηθούν στο ιατρείο, παρέχοντας γρήγορα πληροφορίες στον κλινικό κτηνίατρο σχετικές με την αιτία της συλλογής. Η γνώση αυτή είναι απαραίτητη για την έγκαιρη και αποτελεσματική θεραπευτική αντιμετώπιση της υποκείμενης παθολογικής κατάστασης.Cases involving pleural and peritoneal effusions occur relatively frequently in clinical practice. Determining the underlying etiology in these cases relies mainly on fluid analysis. The technique used for obtaining the pleural or peritoneal fluid can impact greatly the results of the analysis. Most often used diagnostic tools include evaluation of gross appearance, Total Nucleated Cell Count / Total Protein (TNCC/TP) measurement, chemical/biochemical analysis (Lactate dehydrogenase and lactate, cholesterol, triglycerides, glucose, creatinine, pH, pO2, pCO2, and K measurements), cytology (identification of septic and non-septic inflammation and neoplasia), microbiology (Gram stain, culture, molecular techniques), and specific tests for certain clinical conditions and diseases. Classifying an effusion as transudate, modified transudate and exudate is traditionally based on the TNCC and TP values. New diagnostic methods encourage the clinician to approach the effusion etiologically instead of strictly following this traditional classification. Many of the diagnostic tests described in this review are simple and can be performed in-house, providing the clinician quickly with information about the cause of the effusion, essential for an effective treatment plan without wasting valuable time