Stability and isotopic dating of monazite and allanite in partially molten rocks: examples from the Central Alps

We investigated the stability of monazite and allanite as a function of bulk rock composition within several types of Tertiary Alpine anatexites, characterized by different compositions and melting reactions, but similar P-T conditions of melting. The investigated rocks consist of: (1) orthogneisses in which the melting reaction was triggered by water infiltration from the Bergell pluton; (2) anatectic tonalites, which were affected by water-assisted melting; and (3) metapelitic migmatites, which underwent muscovite dehydration melting. The studied anatexites cover a large range of Ca contents and water activities during partial melting, and allow an assessment of how much these parameters affect the stability of accessory phases. The different melting reactions that affected these rocks generated different water activities during the melt-present stage; they were highest in the water-saturated, contact metamorphic anatexites, and lowest in the metapelitic anatexites that underwent dehydration melting. These differences go together with different accessory phases within the migmatites. Whereas metapelitic anatexites only contain monazite, anatexites derived from tonalitic and granodioritic protoliths mainly contain allanite. This is consistent with observations made on Tertiary Alpine anatexites, suggesting that the growth of specific accessory phases is determined by the water activity and Ca content during melting. We measured single-grain monazite U/Pb isotope ages. One grain has relics of old cores, which have also been detected in Y-zonation patterns of the monazite. The data of unzoned monazites indicate partial melting in the Southern Steep Belt between 30.78 ± 0.14 and 28.10 ± 0.28M

The Tauern Window (Eastern Alps, Austria): a new tectonic map, with cross-sections and a tectonometamorphic synthesis

We present a tectonic map of the Tauern Window and surrounding units (Eastern Alps, Austria), combined with a series of crustal-scale cross-sections parallel and perpendicular to the Alpine orogen. This compilation, largely based on literature data and completed by own investigations, reveals that the present-day structure of the Tauern Window is primarily characterized by a crustal-scale duplex, the Venediger Duplex (Venediger Nappe system), formed during the Oligocene, and overprinted by doming and lateral extrusion during the Miocene. This severe Miocene overprint was most probably triggered by the indentation of the Southalpine Units east of the Giudicarie Belt, initiating at 23-21Ma and linked to a lithosphere-scale reorganization of the geometry of mantle slabs. A kinematic reconstruction shows that accretion of European lithosphere and oceanic domains to the Adriatic (Austroalpine) upper plate, accompanied by high-pressure overprint of some of the units of the Tauern Window, has a long history, starting in Turonian time (around 90Ma) and culminating in Lutetian to Bartonian time (45-37Ma

Kinematics of the SEMPfault in the western Tauern Window (Stillupp Valley)

The working area is located in the Stillupp Valley (Tirol, Austria), where the western termination of the SEMPfault (Salzach, Ennstal, Mariazell, Puchberg), overprints the northernmost margin of the Zentralgneiss. This sinistral shearzone, which has a length of about 300 km, and causes a lateral displacement of 60km (Linzer et al. 2002), marks part of the northern border of the Tauern Window...conferenc

Windows over a New Low Energy Axion

We outline some general features of possible extensions of the Standard Model that include anomalous U(1) gauge symmetries, a certain number of axions and their mixings with the CP-odd Higgs sector. As previously shown, after the mixing one of the axions becomes a physical pseudoscalar (the axi-Higgs) that can take the role of a modified QCD axion. It can be driven to be very light by the same non-perturbative effects that are held responsible for the solution of the strong CP-problem. At the same time the axi-Higgs has a sizeable gauge interaction, which is not allowed to the Peccei-Quinn axion, possibly explaining the PVLAS results. We point out that the Wess-Zumino term, typical of these models, can be both interpreted as an anomaly inflow from higher dimensional theories (second window) but also as a result of partial decoupling of an extra Higgs sector (and of a fermion) that leaves behind an effective anomalous abelian theory (first window) in a broken St\"{u}ckelberg phase. The possibility that the axi-Higgs can be heavy, of the order of the Higgs mass or larger, however, can't be excluded. The potentialities for the discovery of this particle and of anomaly effects in the neutral current sector at the LHC are briefly discussed in the context of a superstring inspired model (second window), but with results that remain valid also if any of the two possibilities is realized in Nature.Comment: 17 pages, 8 Figs, replaced with revised final version, to appear on Phys.Lett.

The Tauern Window (Eastern Alps, Austria): a new tectonic map, with cross-sections and a tectonometamorphic synthesis

We present a tectonic map of the Tauern Window and surrounding units (Eastern Alps, Austria), combined with a series of crustal-scale cross-sections parallel and perpendicular to the Alpine orogen. This compilation, largely based on literature data and completed by own investigations, reveals that the present-day structure of the Tauern Window is primarily characterized by a crustal-scale duplex, the Venediger Duplex (Venediger Nappe system), formed during the Oligocene, and overprinted by doming and lateral extrusion during the Miocene. This severe Miocene overprint was most probably triggered by the indentation of the Southalpine Units east of the Giudicarie Belt, initiating at 23–21 Ma and linked to a lithosphere-scale reorganization of the geometry of mantle slabs. A kinematic reconstruction shows that accretion of European lithosphere and oceanic domains to the Adriatic (Austroalpine) upper plate, accompanied by high-pressure overprint of some of the units of the Tauern Window, has a long history, starting in Turonian time (around 90 Ma) and culminating in Lutetian to Bartonian time (45–37 Ma)

Stuckelberg Axions and the Effective Action of Anomalous Abelian Models 2. A SU(3)_C x SU(2)_W x U(1)_Y x U(1)_B model and its signature at the LHC

We elaborate on an extension of the Standard Model with a gauge structure enlarged by a single anomalous U(1), where the presence of a Wess-Zumino term is motivated by the Green-Schwarz mechanism of string theory. The additional gauge interaction is anomalous and requires an axion for anomaly cancelation. The pseudoscalar implements the St\"{u}ckelberg mechanism and undergoes mixing with the standard Higgs sector to render the additional U(1) massive. We consider a 2-Higgs doublet model. We show that the anomalous effective vertices involving neutral currents are potentially observable. We clarify their role in the case of simple processes such as $Z^*\to \gamma \gamma$, which are at variance with respect to the Standard Model. A brief discussion of the implications of these studies for the LHC is included.Comment: 50 pages, 16 figures, replaced with revised final versio

Anomaly Poles as Common Signatures of Chiral and Conformal Anomalies

One feature of the chiral anomaly, analyzed in a perturbative framework, is the appearance of massless poles which account for it. They are identified by a spectral analysis of the anomaly graph and are usually interpreted as being of an infrared origin. Recent investigations show that their presence is not just confined in the infrared, but that they appear in the effective action under the most general kinematical conditions, even if they decouple in the infrared. Further studies reveal that they are responsible for the non-unitary behaviour of these theories in the ultraviolet (UV) region. We extend this analysis to the case of the conformal anomaly, showing that the effective action describing the interaction of gauge fields with gravity is characterized by anomaly poles that give the entire anomaly and are decoupled in the infrared (IR), in complete analogy with the chiral case. This complements a related analysis by Giannotti and Mottola on the trace anomaly in gravity, in which an anomaly pole has been identified in the corresponding correlator using dispersion theory in the IR. Our extension is based on an exact computation of the off-shell correlation function involving an energy-momentum tensor and two vector currents (the gauge-gauge-graviton vertex) which is responsible for the appearance of the anomaly.Comment: 13 pages, 4 figures revised final version, to appear on Phys. Lett.

Rare deleterious germline variants and risk of lung cancer

Recent studies suggest that rare variants exhibit stronger effect sizes and might play a crucial role in the etiology of lung cancers (LC). Whole exome plus targeted sequencing of germline DNA was performed on 1045 LC cases and 885 controls in the discovery set. To unveil the inherited causal variants, we focused on rare and predicted deleterious variants and small indels enriched in cases or controls. Promising candidates were further validated in a series of 26,803 LCs and 555,107 controls. During discovery, we identified 25 rare deleterious variants associated with LC susceptibility, including 13 reported in ClinVar. Of the five validated candidates, we discovered two pathogenic variants in known LC susceptibility loci, ATM p.V2716A (Odds Ratio [OR] 19.55, 95%CI 5.04–75.6) and MPZL2 p.I24M frameshift deletion (OR 3.88, 95%CI 1.71–8.8); and three in novel LC susceptibility genes, POMC c.*28delT at 3′ UTR (OR 4.33, 95%CI 2.03–9.24), STAU2 p.N364M frameshift deletion (OR 4.48, 95%CI 1.73–11.55), and MLNR p.Q334V frameshift deletion (OR 2.69, 95%CI 1.33–5.43). The potential cancer-promoting role of selected candidate genes and variants was further supported by endogenous DNA damage assays. Our analyses led to the identification of new rare deleterious variants with LC susceptibility. However, in-depth mechanistic studies are still needed to evaluate the pathogenic effects of these specific alleles