5,661 research outputs found

    Observability of MSSM Higgs bosons via sparticle decay modes in CMS

    Get PDF
    We discuss the possibilities to observe the decays of heavy SUSY Higgs bosons into supersymmetric particles at the LHC. Such an observation would be of interest either in a discovery search if sparticle modes are the dominant ones, or in a study of additional decay modes, bringing information on the SUSY scenario potentially at work. We will focus on the most promising channel where the heavy neutral Higgses decay into a pair of next-to-lightest neutralinos, followed by their decay into two leptons and the LSP, thus leading to four isolated leptons + missing E_T as the main final state signature. A study with the CMS detector shows that the background (SM + SUSY) can be sufficiently suppressed and that in the mass region between m_A = 230 and 450 GeV, for low and intermediate values of tan beta, the signal would be visible provided neutralinos and sleptons are light enough.Comment: 14 pages, 20 figure

    Searching for Higgs Bosons in Association with Top Quark Pairs in the H -> bb Decay Mode

    Full text link
    Search for the Higgs Boson is one of the prime goals of the LHC. Higgs bosons lighter than 130 GeV decay mainly to a b-quark pair. While the detection of a directly produced Higgs boson in the bb channel is impossible because of the huge QCD background, the channel ttH -> lnqqbbbb is very promising in the Standard Model and the MSSM. We discuss an event reconstruction and selection method based on likelihood functions. The CMS detector response is performed with parametrisations obtained from detailed simulations. Various physics and detector performance scenarios are investigated and the results are presented. It turns out that excellent b-tagging performance and good mass resolution are essential for this channel.Comment: 10 pages, 6 figure

    Prospects for Higgs Boson Searches in the Channel WH -> lnbb

    Get PDF
    We present a method how to detect the WH -> lnbb in the high luminosity LHC environment with the CMS detector. This study is performed with fast detector response simulation including high luminosity event pile up. The main aspects of reconstruction are pile up jet rejection, identification of b-jets and improvement of Higgs mass resolution. The detection potential in the SM for m(H) < 130 GeV and in the MSSM is only encouraging for high integrated luminosity. Nevertheless it is possible to extract important Higgs parameters which are useful to elucidate the nature of the Higgs sector. In combination with other channels, this channel provides valuable information on Higgs boson couplings.Comment: 8 pages, 8 figure

    Spatial mapping of splicing factor complexes involved in exon and intron definition

    Get PDF
    We have analyzed the interaction between serine/arginine-rich (SR) proteins and splicing components that recognize either the 5′ or 3′ splice site. Previously, these interactions have been extensively characterized biochemically and are critical for both intron and exon definition. We use fluorescence resonance energy transfer (FRET) microscopy to identify interactions of individual SR proteins with the U1 small nuclear ribonucleoprotein (snRNP)–associated 70-kD protein (U1 70K) and with the small subunit of the U2 snRNP auxiliary factor (U2AF35) in live-cell nuclei. We find that these interactions occur in the presence of RNA polymerase II inhibitors, demonstrating that they are not exclusively cotranscriptional. Using FRET imaging by means of fluorescence lifetime imaging microscopy (FLIM), we map these interactions to specific sites in the nucleus. The FLIM data also reveal a previously unknown interaction between HCC1, a factor related to U2AF65, with both subunits of U2AF. Spatial mapping using FLIM-FRET reveals differences in splicing factors interactions within complexes located in separate subnuclear domains

    Summary of the CMS Discovery Potential for the MSSM SUSY Higgses

    Full text link
    This work summarises the present understanding of the expected MSSM SUSY Higgs reach for CMS. Many of the studies presented here result from detailed detector simulations incorporating final CMS detector design and response. With 30 fb-1 the h -> gamma,gamma and h -> bb channels allow to cover most of the MSSM parameter space. For the massive A,H,H+ MSSM Higgs states the channels A,H -> tau,tau and H+ -> tau,nu turn out to be the most profitable ones in terms of mass reach and parameter space coverage. Consequently CMS has made a big effort to trigger efficiently on taus. Provided neutralinos and sleptons are not too heavy, there is an interesting complementarity in the reaches for A,H -> tau,tau and A,H -> chi,chi.Comment: 19 pages, 27 figure

    Muon Track Matching

    Get PDF
    For most physical processes the tracks observed in the muon stations must be matched with the corresponding tracks in the inner tracker, the external muon system providing muon identification and triggering but the tracker points giving the precise momentum measurement at lower momenta. For high momenta the momentum resolution is much improved by the interconnection of inner and outer measurements. The matching of outer and inner measurements is more delicate in case of muons embedded in jets. A study of the matching procedure was carried out using samples of (b, anti b) jets at high Pt, requiring (b, anti b) -> mu decays.For most physical processes the tracks observed in the muon stations must be matched with the corresponding tracks in the inner tracker, the external muon system providing muon identification and triggering but the tracker points giving the precise momentum measurement at lower momenta. For high momenta the momentum resolution is much improved by the interconnection of inner and outer measurements. The matching of outer and inner measurements is more delicate in case of muons embedded in jets. A study of the matching procedure was carried out using samples of (b, anti b) jets at high Pt, requiring (b, anti b) -> mu decays

    Dark Matter and LHC: What is the Connection?

    Get PDF
    We review what can (and cannot) be learned if dark matter is detected in one or more experiments, emphasizing the importance of combining LHC data with direct, astrophysical and cosmological probes of dark matter. We briefly review the conventional picture of a thermally produced WIMP relic density and its connection with theories of electroweak symmetry breaking. We then discuss both experimental and theoretical reasons why one might generically expect this picture to fail. If this is the case, we argue that a combined effort bringing together all types of data -- combined with explicitly constructed theoretical models -- will be the only way to achieve a complete understanding of the dark matter in our universe and become confident that any candidate actually provides the relic density.Comment: 25 pages, 2 figures, Invited review for Modern Physics Letters

    Biopolitical Marketing and Technologies of Enclosure

    Get PDF
    Recently, there has been a lot of talk about consumer empowerment through new information and communication technologies. Corporate captains of marketing, Wired Magazine’s neo-libertarian techno-utopians, marketing consultants of the digital economy and many marketing academics agree that we all have more choices, more information, more entertainment, more transparency, and lower prices thanks to Amazon, Facebook, Youtube, and all the rest. We are liberated from the burdens of material ownership, free to access digital objects and services in ways that satisfy our needs in highly targeted and efficient ways. The empowerment through technology chorus is so loud and cohesive that we generally take the message for granted. And in some limited respect, consumers may feel empowered when shopping on Amazon.com or in the malls with their iPhones on hand. But let us be very clear about the idea of empowerment that is promoted by the cheerleaders of what Jodi Dean (2005) calls communicative capitalism. Real empowerment, so much should be clear, will never be “granted” to consumers by those in economic (and thus political) power. In the final analysis – and putting aside for a moment the fact that even empowered consumers are still interpellated first and foremost as subjects of consumption – the ideal of the empowered consumer (rational, enlightened, informed, restrained, un-manipulable) is completely antithetical to the needs of capital and the marketing regime within consumer capitalism. Therefore, any call for actual consumer empowerment would automatically be a radical demand and an insurgent claim aimed at undermining and replacing capital’s power to dominate the consumer totally. In the end, it is important to recognize that any technology employed by marketing today becomes a technology of enclosure (even if never completely successful), which permits empowerment only in a version sanction by capital. That is why marketing (and capital more generally [see Lazzarato, 2004]) today is biopolitical. It wants to govern life completely while appearing to not govern at all. In this chapter we argue that new technologies in contemporary marketing management are best thought of as technologies of enclosure. On the one hand, marketing encloses the subject as individualized and individuated consumer. On the other, marketing aims to enclose (ie., capture, make proprietary, appropriate) what is common or collectively produced or cherished by individuals as inalienable expressions of personal identity and agency. At the same time that marketing encloses, it operates ideologically, although not in the classical Marxist sense of creating a false consciousness. Rather, the challenge for marketers is to enclose and capture the subject and the common while appearing not to do any of these things. By accepting as non-ideological terms such as choice, identity, fulfillment, empowerment, enrichment, collaboration, creativity and so on, marketers and consumers alike choose to believe, just as anyone sensible would believe, that new techniques and technologies of enclosure are really just good marketing practice aimed at value creation and delivery, not customer domination and exploitation. We should remember that an atmosphere of distrust has accompanied the development of marketing from the beginning and marketers have long been suspected of being professional manipulators, devising salacious techniques and technologies with which to incite, manipulate and exploit consumer desire and anxiety. As Packard put it fifty years ago, “[T]hese depth manipulators are in their operations beneath the surface of conscious life, starting to acquire a power of persuasion that is becoming a matter of justifiable public scrutiny and concern” (1957, pp. 9-10). More recent popular indictments of marketing include Adam Curtis’s documentaries on The Century of the Self, Naomi Klein’s No Logo (2000), and the BBC series The Men Who Makes Us Spend (presented by Jacques Peretti). Criticism of marketers is compounded by widespread consumer cynicism regarding the genuineness of marketing messages (see Gabriel and Lang, 1995). Interestingly, the emerging generation of online marketers– typically referred to as digital or social media marketers – see marketing’s crisis of legitimacy directly tied to what it considers the corporate, top-down marketing methods devised in the 1970s and 1980s and designed to discipline and control consumers. For a new generation of tech-savvy marketers, imbued with a solid dose of techno-libertarian ideals of independence and a frontier mentality that rejects top-down authority and bureaucracy in favor of self-organizing systems, radical autonomy and freely collaborative networks, a dramatic shift in mindset was needed in the age of participatory media and Big Data. In a radical turn propagated, for example, by prominent social media marketing experts like Solis (2010) and Stratten (2010), marketing has to be ‘un’-done. The term ‘un-marketing’ rises to prominence in the consulting literature and offers a reframing of marketing that rejects corporate-controlled top-down techniques, and favours horizontal, collaborative, and participatory customer engagement (Kutcher, 2010, Stratten, 2010, 2014). In this context, the idea of online customer communities gains popularity because it provides a fantasy of restructuring marketplace relations according to principles of co-creation, sovereignty, equality, and sharing. More recently, what we call Big Data marketing is framed according to similar registers where data magnetizes consumers and marketers to a shared ethos of the “opt-in” economy (Godin, 1999). Big Data marketers – at least in the version propagated by Google’s Hal Varian, for example – pose innocuously enough as personal recommendation and consulting agents for consumers who in return for giving up personal information receive ever more relevant, valuable, and desired information, goods and services (Zuboff, 2015). Who would not like such a deal that appears to be based on liberal ideals of good intentions on all sides and the equal distribution of costs and benefits, even as companies manage communities and customer data not on behalf of consumers but on behalf of corporate profit. In sum, new marketing technologies – from blogs to communities to surveillance-based collaborative filtering and recommender systems – no matter how invasive, ever-present and insidious, have been framed by technology-driven marketers as democratizing and equalizing forces reshaping the contemporary marketplace in favor of the consumer. Customer and brand communities are happy places of collaboration and collective value creation governed by an ethos of mutual respect, sharing and dispersed control. Big Data Marketing, which aspires to intensifying consumer surveillance and control (Zuboff, 2015), is often presented as part of the contemporary ethos of collaborative ‘in-this-together-ness’ and collective support structures between companies and consumers. Marketers are asked to employ Big Data to better understand, assist, support and connect with customers; the technology magnetizing both exchange parties to a fantasy of better products, better choices, better experiences, better prices, better service and generally happier lives. To live in a world where companies strain to innovate and please consumers, all we need to do in return is give companies complete access to our personal information. Such a request makes sense to a generation of marketing professionals and consumers that have grown up with Google, Facebook and Amazon tracking its every move. In the next section we explore critically new marketing technologies such as online customer communities and Big Data, and possession of digital objects as consumer lock in. .We suggest that these technologies are technologies of Biopolitical Marketing. They aspire to enclose all forms of life for profit. We suggest that marketing innovation is now structured according to the imperative of biopolitical marketing: the making, valorizing and enclosing of all forms and expressions of life

    Searching for Higgs bosons in association with top quark pairs in the H0 -> bb decay mode [online]

    Get PDF
    Search for the Higgs Boson is one of the prime goals of the LHC. Higgs bosons lighter than 130 GeV/c2 decay mainly to a b­quark pair. While the detection of a directly produced Higgs boson in the bb channel is impossible because of the huge QCD background, the channel ttH0 --> l±vqqbbbb is very promising in the Standard Model and the MSSM. We discuss an event reconstruction and selection method based on likelihood functions. The CMS detector response is performed with parametrisations obtained from detailed simulations. Various physics and detector performance scenarios are investigated and the results are presented. It turns out that excellent b­tagging performance and good mass resolution are essential for this channel
    corecore