Zeitschriftenartikel zum Thema „Pile-up rejection“

Abstract DANTE is a new Digital Pulse Processor (DPP) developed for fluorescence detectors, like Silicon Drift Detectors (SDDs) or High Purity Germanium detectors (HPGe), used in X-ray Fluorescence (XRF) and X-ray Absorption Spectroscopy (XAS) experiments at synchrotron facilities. Its main features are its optimal energy resolution and peak stability for detector count rate values up to 1–2 Mcps, and its enhanced rejection of pile-up events. In this paper, we present the first complete evaluation of DANTE performance in SOLEIL synchrotron facility. DANTE has been tested in laboratory with an X-ray generator source and in different experiments at LUCIA and PUMA beamlines at SOLEIL.

The Run 3 of the Large Hadron Collider (LHC) will be characterised by an enhanced level of noise in the CMS electromagnetic calorimeter (ECAL), caused by the ageing of the photosensors and the loss of crystal transparency due to radiation damage. To face these new conditions, some parameters of the clustering algorithms of the ECAL, namely the Particle-Flow Clustering and SuperClustering algorithms, are tuned to offer optimal performance in terms of signal preservation and noise and pile-up rejection. The methods used for the tuning as well as its performance are presented.

The pre-amplifier with an active reset system was examined to carry out PIXE analysis under the condition that X-rays and back scattered protons are detected simultaneously. Rejection of false signals produced by back scattered protons is discussed, and it is confirmed that false signals can be completely rejected by using an inhibit signal of the preamplifier. Energy resolution of an X-ray detector and a live-time of measurement system were measured as a function of counting rate. As a result, energy resolution did not change and the live-time was 70 % at the high counting rate over 3kcps. The pile-up effect on the X-ray signal with the proton signal tail is also discussed.

We report the development of a CaMoO4crystal low temperature detector for the AMoRE neutrinoless double beta decay(0νββ)search experiment. The prototype detector cell was composed of a 216 g CaMoO4crystal and a metallic magnetic calorimeter. An overground measurement demonstrated FWHM resolution of 6–11 keV for full absorption gamma peaks. Pulse shape discrimination was clearly demonstrated in the phonon signals, and 7.6 σof discrimination power was found for theαandβ/γseparation. The phonon signals showed rise-times of about 1 ms. It is expected that the relatively fast rise-time will increase the rejection efficiency of two-neutrino double beta decay pile-up events which can be one of the major background sources in0νββsearches.

Abstract A typical problem in low-level liquid scintillation (LS) counting is the identification of α particles in the presence of a high background of β and γ particles. Especially the occurrence of β-β and β-γ pile-ups may prevent the unambiguous identification of an α signal by commonly used analog electronics. In this case, pulse-shape discrimination (PSD) and pile-up rejection (PUR) units show an insufficient performance. This problem was also observed in own earlier experiments on the chemical behaviour of transactinide elements using the liquid-liquid extraction system SISAK in combination with LS counting. α-particle signals from the decay of the transactinides could not be unambiguously assigned. However, the availability of instruments for the digital recording of LS pulses changes the situation and provides possibilities for new approaches in the treatment of LS pulse shapes. In a SISAK experiment performed at PSI, Villigen, a fast transient recorder, a PC card with oscilloscope characteristics and a sampling rate of 1 giga samples s−1 (1 ns per point), was used for the first time to record LS signals. It turned out, that the recorded signals were predominantly α, β-β and β-γ pile up, and fission events. This paper describes the subsequent development and use of artificial neural networks (ANN) based on the method of “back-propagation of errors” to automatically distinguish between different pulse shapes. Such networks can “learn” pulse shapes and classify hitherto unknown pulses correctly after a learning period. The results show that ANN in combination with fast digital recording of pulse shapes can be a powerful tool in LS spectrometry even at high background count rates.

The Large Hadron Collider (LHC) is being prepared for an extensive upgrade to boost its particle discovery potential. The new phase, High Luminosity LHC, will operate at a factor-of-five-increased luminosity (the number proportional to the rate of collisions). Consequently, such an increase in luminosity will result in enormous quantities of generated data that cannot be transmitted or stored with the currently available resources and time. However, the vast majority of the generated data consist of uninteresting data or pile-up data containing few interesting events or electromagnetic showers. High-Luminosity LHC detectors, including the Compact Muon Solenoid (CMS), will thus have to rely on innovative approaches like the proposed one to select interesting collision data. In charge of data reduction/selection at the early stages of data streaming is a level 1 trigger (L1T), a real-time event selection system. The final step of the L1T is a global trigger, which uses sub-system algorithms to make a final decision about signal acceptance/rejection within a decision time of around 12 microseconds. For one of these sub-system L1T algorithms, we propose using quantized neural network models deployed in targeted L1T devices, namely, field-programmable gate arrays (FPGA), as a classifier between electromagnetic and pile-up/quantum chromodynamics showers. The developed quantized neural network operates in an end-to-end manner using raw detector data to speed up the classification process. The proposed data reduction methods further decrease model size while retaining accuracy. The proposed approach was tested with simulated data (since the detector is still in the production stage) and took less than 1 microsecond, achieving real-time signal–background classification with a classification accuracy of 97.37% for 2-bit-only quantization and 97.44% for quantization augmented with the data reduction approach (compared to 98.61% for the full-precision, standard network ).

Semiconductor energy dispersive spectrometers (EDS), the most commonly used detectors for x-ray microanalysis, have matured to the point that significant improvement in energy resolution is not expected in the future. We believe a revolutionary advance in x-ray microanalysis will occur in the next few years due to the development of new x-ray spectrometers based on microcalorimeters. Energy resolution comparable with wavelength dispersive spectrometers, 3 eV to 10 eV, has already been achieved; future detectors may reach a fundamental limit as low as 0.5 eV to 1 eV.In a microcalorimeter, the energy of an x-ray is converted into heat, and a measurement of the temperature rise of the detector gives the deposited photon energy. Our microcalorimeter detector consists of a superconducting transition edge thermometer cooled to an operating temperature of 100 mK by a compact adiabatic demagnetization refrigerator, a read-out SQUID (Superconducting Quantum Interference Device) preamplifier followed by pulse-shaping amplifier and pile-up rejection circuitry, and a multi-channel analyzer with real-time computer interface.

Silicon drift detector (SDD) is a kind of high performance X-ray detector, which is widely used. The ray detection system based on SDD is composed of SDD device, preamplifier and pulse processing system. The now available pulse processing system has the problems of poor pulse pile-up rejection performance and being vulnerable to the parameter fluctuations of front-end system, which degrades the performance of detection system. A digital pulse processing system is proposed. In this system, analog-to-digital converter (ADC) directly samples the output signal of preamplifier, and transmits the data to the digital pulse processing platform for processing. According to the signal characteristics of SDD device and preamplifier, the influence of ADC sampling bits and sampling frequency on system performance is analyzed. Two optimized ADC sampling circuits are proposed to reduce energy resolution degradation induced by insufficient ADC sampling bits. The pulse shaping algorithm in the digital pulse processing system is studied. The results show that the shaping signal will not be distorted due to the parameter fluctuations of the front-end system, which proves the robustness of the digital pulse processing system. The digital pulse processing system is implemented and tested, and the correctness of the system is verified.

Si(Li) and Ge Energy Dispersive Spectroscopy (EDS) detectors are commonly used for x-ray microanalysis because they are easy to use, inexpensive to operate, and offer both rapid qualitative evaluation of chemical composition and accurate quantitative analysis. Unfortunately, they are limited by energy resolutions on the order of 100 eV, which is insufficient to resolve many important overlapping x-ray peaks in materials of industrial interest, such as the Si Kα and W Mα peak overlap in WSi2. Although WDS spectrometers with excellent energy resolution (typically 2 eV to 10 eV) can resolve most peak overlaps, qualitative WDS analysis is limited by the need to serially scan over the entire energy range using multiple diffraction crystals. There is a need for a new generation of x-ray spectrometers for microanalysis that combines the excellent energy resolution of WDS spectrometers with the ease of use and the parallel energy detection capability of EDS spectrometers.We are developing a high-energy-resolution x-ray microcalorimeter spectrometer for use in x-ray microanalysis. Our microcalorimeter spectrometer consists of a superconducting transition-edge microcalorimeter cooled to an operating temperature of 100 mK by a compact adiabatic demagnetization refrigerator mounted on a SEM column, read-out SQUID (Superconducting Quantum Interference Device) electronics followed by pulse-shaping amplifiers and pile-up rejection circuitry, and a multichannel analyzer with real-time computer interface.

AbstractCUORE Upgrade with Particle IDentification (CUPID) is a foreseen ton-scale array of Li2MoO4 (LMO) cryogenic calorimeters with double readout of heat and light signals. Its scientific goal is to fully explore the inverted hierarchy of neutrino masses in the search for neutrinoless double beta decay of 100Mo. Pile-up of standard double beta decay of the candidate isotope is a relevant background. We generate pile-up heat events via injection of Joule heater pulses with a programmable waveform generator in a small array of LMO crystals operated underground in the Laboratori Nazionali del Gran Sasso, Italy. This allows to label pile-up pulses and control both time difference and underlying amplitudes of individual heat pulses in the data. We present the performance of supervised learning classifiers on data and the attained pile-up rejection efficiency.

AbstractOne of the primary obstacles faced by spectrometers operating under high counting rates is pile-up, which occurs when two or more events are detected within a timelapse short enough to result in a superposition of the events waveforms. These can not hence be integrated separately in order to get their amplitudes. Piled-up events are typically identified using pile-up rejection or recovery algorithms. In the latter case, the constituent single waveforms and their amplitudes are also restored. However, there are instances in which the pulses overlap so closely that it is impossible to identify the occurrence of pile-up, resulting in the integration of these pulses into a single spurious event. This phenomenon is known as degenerate pile-up. A method to rectify the incorrect reconstruction of degenerate pile-up was developed, based on a statistical approach, which can be directly applied to the pulse height spectra distributions. The approach was tested on a number of synthetic spectra, with counting rates ranging from 20 kHz up to 1 MHz. The recovered spectra were compared to those purely analysed with a pile-up recovery algorithm, demonstrating an improvement of the reconstructed spectrum of several tens of percent when compared to the true synthetic counterpart.

AbstractRandom coincidences of events could be one of the main sources of background in the search for neutrino-less double-beta decay of $$^{100}$$ 100 Mo with macro-bolometers, due to their modest time resolution. Scintillating bolometers as those based on Li$$_2$$ 2 MoO$$_4$$ 4 crystals and employed in the CROSS and CUPID experiments can eventually exploit the coincident fast signal detected in a light detector to reduce this background. However, the scintillation provides a modest signal-to-noise ratio, making difficult a pile-up pulse-shape recognition and rejection at timescales shorter than a few ms. Neganov–Trofimov–Luke assisted light detectors (NTL-LDs) offer the possibility to effectively increase the signal-to-noise ratio, preserving a fast time-response, and enhance the capability of pile-up rejection via pulse shape analysis. In this article we present: (a) an experimental work performed with a Li$$_2$$ 2 MoO$$_4$$ 4 scintillating bolometer, studied in the framework of the CROSS experiment, and utilizing a NTL-LD; (b) a simulation method to reproduce, synthetically, randomly coincident two-neutrino double-beta decay events; (c) a new analysis method based on a pulse-shape discrimination algorithm capable of providing high pile-up rejection efficiencies. We finally show how the NTL-LDs offer a balanced solution between performance and complexity to reach background index $$\sim $$ ∼ $$10^{-4}$$ 10 - 4 counts/keV/kg/year with 280 g Li$$_2$$ 2 MoO$$_4$$ 4 ($$^{100}$$ 100 Mo enriched) bolometers at 3034 keV, the Q$$_{\beta \beta }$$ β β of the double-beta decay, and target the goal of a next generation experiment like CUPID.

Introduction Geothermal energy piles (GEPs) are foundation elements that are installed in the ground to support the weight of the building to a competent strata. Energy loops are installed into the piles to allow heat rejection or extraction via the circulation of fluid through the loops. In winter, low-grade heat is extracted from the ground (source) and transferred to the building (sink) to achieve space heating. Conversely, in summer, heat is removed from the building and rejected into the ground to achieve space cooling. The system relies on the temperature gradient between the ground and the ambient air temperature; where in winter, the ground temperature is higher than the air temperature, while in summer, the opposite is true. Thus, the system can sustainably and continuously supply the heating and/or cooling demand of a building once the temperature gradient between the ambient air and the ground is maintained. To improve the sustainability and performance of the system, the heat energy rejected into the ground can be stored and used at a later time when space heating is required [1]. Energy storage substances such as phase change materials (PCMs) can be incorporated into energy piles to store the heat that is rejected into the ground to improve the performance of the GEP system [2]. PCMs are materials that stores or releases heat energy during phase transition. Many researchers including [3,4] have reported using PCMs in buildings to improve thermal comfort and minimise the energy demand during heating and cooling periods, however, not much work has been done with regard to incorporating them into pile foundations to improve the performance of GEP systems. Thus, this study carried out a laboratory experiment to investigate the effect of the addition salt hydrate PCM on the energy performance of geothermal energy piles. Laboratory test and procedure In this study, lab-scaled models of energy piles were constructed, with and without PCM. The piles are characterised by a length and a diameter of 300 mm and 100 mm, respectively. In order to add PCM into the piles, the PCM was encased and sealed in a PVC tube with an inner and an outer diameter of 6mm and 8mm, respectively. The same size of PVC tube was used for the energy loops. The energy loop (U-shape), and the encased PCM incorporated tubes are attached together and placed in the mould prior to concreting, for the pile model with PCM (see Figure 1a). Whereas only the energy loop was installed in the control sample. In the test setup, a layer of sand (220mm thick) was placed and compacted in an insulated wooden box (520mm × 520mm × 520mm). Afterwards, the pile was then installed at the center of the box and then filled with sand, in layers and compacted. An insulation sheet was used to cover the top of the box to prevent heat loss and the ambient air temperature influencing the tests’ results. Water at a temperature of 32°C, was circulated through the pile continuously for a duration of 4 days (96 hours). Instrumentations were installed in the pile and soil to monitor and record the changes in temperature during the tests (see Figure 1b). Results and discussion Figure 1c shows the results comparing the average energy rejected, and stored, in the ground for the piles with and without PCM. The maximum heat energy stored at the beginning of the test was found to be about 460W and 360W for the control and PCM piles. However, at the end of the tests, the energy stored was 230W and 430W for the control and PCM pile, with an average energy stored as shown in Table 1. The addition of salt hydrate PCM absorbs the heat rejected into the pile, consequently improving its thermal performance by about 22% in comparison to the control pile. Similarly, the magnitude of temperature developed in the pile and surrounding soil were observed to be lower in the pile with PCM. This can ultimately reduce the induced stresses and strains induced in a pile due to heat energy extraction or rejection. Conclusion This paper investigated the feasibility of using salt hydrate PCM in energy piles for heat storage. It was found that the energy rejected in a pile with PCM increases by up to 22% compared to a non-PCM pile.

AbstractSeveral improvements to the ATLAS triggers used to identify jets containing b-hadrons (b-jets) were implemented for data-taking during Run 2 of the Large Hadron Collider from 2016 to 2018. These changes include reconfiguring the b-jet trigger software to improve primary-vertex finding and allow more stable running in conditions with high pile-up, and the implementation of the functionality needed to run sophisticated taggers used by the offline reconstruction in an online environment. These improvements yielded an order of magnitude better light-flavour jet rejection for the same b-jet identification efficiency compared to the performance in Run 1 (2011–2012). The efficiency to identify b-jets in the trigger, and the conditional efficiency for b-jets that satisfy offline b-tagging requirements to pass the trigger are also measured. Correction factors are derived to calibrate the b-tagging efficiency in simulation to match that observed in data. The associated systematic uncertainties are substantially smaller than in previous measurements. In addition, b-jet triggers were operated for the first time during heavy-ion data-taking, using dedicated triggers that were developed to identify semileptonic b-hadron decays by selecting events with geometrically overlapping muons and jets.

Last year, the ABC’s Media Watch (17 Oct. 2005) noted the continuing outrage in the tabloid media over “the dirtiest house in NSW”. The program took issue with Sydney newspaper The Daily Telegraph, and the descriptor “exclusive” attached to their article on a property in beachside Bondi (9 Oct. 2005). In fact, as Media Watch pointed out, Channel Seven’s current affairs flagship Today Tonight had already made repeat visits to the residence. A Current Affair, Channel Nine’s rival show, as well as Bondi’s local newspaper also offered coverage. However, I am interested not in the number of times the story appeared – though this is certainly a symptom of what I do want to talk about. Instead, I want to consider the affect generated by this reportage. In turn, I want to consider what this reveals about our attitudes to refuse, and how these attitudes work to constitute social order in capitalist discourse. The overwhelming affective register of the language deployed to speak about the house is disgust. Adam Bell in The Sunday Telegraph paints a visceral picture entitled “A stinking mess”. He writes that the Bondi premises are engulfed in a stinking three-metre high pile of decaying rubbish that poses a serious health and safety risk. … Stacked with empty boxes, beer cartons, broken furniture, canned fruit, newspapers and cardboard, the waste dump fills the entire front and backyards of the house and spills onto the street. On hot days, the stench of the rotting garbage is detected blocks away while at night, rats and cockroaches are regularly seen running in and out of the mess. … The rubbish is piled so high only the roof of the 1920s Californian bungalow is clearly visible from the front. (9 Oct. 2005) Bell’s follow-up speaks of “the huge pile of filth at the infamous Bondi rubbish house” and of “a team of cleaners dressed in forensic ‘space suits’” (27 Nov. 2005). Other News Limited journalists who subsequently visited the site conjured similar imagery (Goldner; Cummings). Television was not to be outdone: Today Tonight called it “the house from hell”, whilst A Current Affair focused on the “disgraceful pile of rat-infested rubbish [that] just gets higher and higher” (Media Watch). The tonality of the language is a dimension of the prevalent discourse of “aspirationalism” that is central to the popularist politics of Australian Prime Minister John Howard. One key signifier of “aspiration” is property ownership expressed through the rhetoric of the “home.” The affective dimension of the reporting—the disgust—stems from the disjuncture of the exalted (Bondi Beach, high property values) and the abject (refuse). It is a tool used to discursively fix the inappropriate physical and social location of the refuse so as to locate what is culturally valued. Bell’s initial article mentions no less than three times in 600 words that the house is a “million dollar property” and is “located in one of Sydney’s most prestigious and expensive suburbs” (9 Oct. 2005). His second article also mentioned the property’s value (27 Nov. 2005), as did another article by a colleague at The Daily Telegraph (9 Dec. 2005). Today Tonight emphasized that the house was in “an exclusive beachside suburb” and that it was “smack bang in the middle of one of Australia’s most expensive and best known suburbs” (Media Watch). William Ian Miller in Anatomy of Disgust explains how the affective response to an encounter like the one with Bondi’s “rubbish house” can be attributed to feelings about organisation. Miller positions disgust as “a strong sense of aversion to something perceived as dangerous because of its danger to contaminate, infect, or pollute by proximity, contact or ingestion” (2). In other words, disgust is the product of an aversion to something that breaches the lines of containment, and therefore signals a threat to established order. The body – a network of physiological and neurological processes, which constitute multiple systems of order in their own right – cannot cope with such a breakdown and reacts accordingly. David Trotter elaborates: Psychological activity [is] an attempt to impose order on experience: bodily paroxysm is a way of confronting and resolving urgent abstract dilemmas. According to this view, you vomit because you have lost confidence in your ability to make sense of the world: your ability to categorize, order, explain, or tell stories about what has happened to you. Disgust is the product of conceptual trauma. (158-9) The “conceptual trauma” in the case of Bondi’s “rubbish house” is a reaction to a transgression of the order of capitalist social space, which then becomes a discursive conduit for its hegemonic renewal. Indeed, the concern with the malfunction in social order that the misplaced refuse represents confirms what anthropologist Mary Douglas has been telling us for some time: If we can abstract pathogenicity and hygiene from our notion of dirt, we are left with the old definition of dirt as matter out of place. This is a very suggestive approach. It implies two conditions: a set of ordered relations and a contravention of that order. Dirt then, is never a unique, isolated event. Where there is dirt there is a system. Dirt is the by-product of a systematic ordering and classification of matter, in so far as ordering involves rejecting inappropriate elements. (36) Certainly, the associated health risks to Mary Bobolas, the house’s owner/occupier, and the wider community from her hoarding are not purely ideological. However, it is impossible to divorce the social discourses surrounding refuse from the series of social and technological developments that Dominique Laporte in his History of Shit calls the “privatisation” of waste (28). The social and technical apparatuses which enable dominant sociogenetic attitudes regarding refuse include the increasing emphasis on private property, the emergence of the family unit as the primary site for the coalescence of socializing forces and inventions such as the toilet (Elias 137-40). Laporte believes that this process in instrumental in creating the individuated, capitalist subject, which, in the context of contemporary Australian capitalist discourse, is the middle-class homeowner. The construction of complex regulatory architecture to manage practices and tastes substantiates American novelist Don DeLillo’s proposal that civilisation did not rise and flourish as men hammered out hunting scenes on bronze gates and whispered philosophy under the stars, with garbage as a noisome offshoot, swept away and forgotten. No, garbage came first, inciting people to build a civilization in response, in self-defense. We had to find ways to discard our waste, to use what we couldn’t discard, to reprocess what we couldn’t use. … Consume or die. That’s the mandate of the culture. And it all ends up in the dump. We make stupendous amounts of garbage, then we react to it, not only technologically but in our hearts and minds. We let it shape us. We let it control our thinking. Garbage comes first, then we build a system to deal with it. (287-8) Most of the systems to which DeLillo refers are designed to counter the visibility of refuse and channel it to a demarcated, separate space. This is the paradox of refuse: our sense of order depends upon it, yet in affluent society we are anxious about confronting it. Over the years, Bondi Beach has been sanitised both materially and socially. The sewage outfall is a heritage site and the area is no longer working class. Yet, it seems the shit is still washing up on the shore: significantly, the refuse Bobolas accumulates is other people’s rubbish collected from “the streets, garbage bins and council clean-ups” (Bell 9 Oct. 2005). It is produced by the very homeowners whose disgust is so palpable. However, the media coverage of the “rubbish house” does not merely remind the rich and famous residents of their own refuse, nor does it function as a critique of conspicuous consumption. The media event of the “rubbish house” illustrates how “matter out of place” and the resulting affect of disgust are exploited discursively by hegemonic culture in order to maintain the ideology of “aspirationalism” and reiterate the wider capitalist project. References Bell, Adam. “A Stinking Mess – Mountain of Garbage in Sydney Yard.” Sunday Telegraph [Sydney] 9 Oct. 2005: 9. Bell, Adam. “End of the Dirt House.” Sunday Telegraph [Sydney] 27 Nov. 2005: 17. Cummings, Larissa. “Bondi Mountain of Rubbish Rises Again.” Daily Telegraph [Sydney] 20 May 2006: 15. DeLillo, Don. Underworld. New York: Scribner, 1997. Douglas, Mary. Purity and Danger: An Analysis of Concepts of Pollution and Taboo. London: Routledge, 2002. Elias, Norbert. The Civilising Process: The History of Manners: Sociogenetic and Psychogenetic Investigations. Trans. Edmund Jephcott. Oxford: Basil Blackwell, 1978. Goldner, Viva. “Rage over Rubbish – Daughters Defend Garbage Mountain.” Daily Telegraph [Sydney] 9 Dec. 2005: 17. Laporte, Dominique. History of Shit. Cambridge, Mass: MIT P, 2002. Media Watch. ABC TV. 17 Oct. 2005. Transcript. 23 Jul 2006 http://www.abc. net.au/mediawatch/transcripts/s1483767.htm. net.au/mediawatch/transcripts/s1483767.htm> Miller, William Ian. The Anatomy of Disgust. Cambridge, Mass & London: Harvard UP, 1997. Trotter, David. Cooking with Mud: The Idea of Mess in Nineteenth-Century Art and Fiction. Oxford: Oxford UP, 2000. Citation reference for this article MLA Style Seale, Kirsten. "Location, Location: Situating Bondi’s “Rubbish House”." M/C Journal 9.5 (2006). echo date('d M. Y'); ?> <http://journal.media-culture.org.au/0610/07-seale.php>. APA Style Seale, K. (Nov. 2006) "Location, Location: Situating Bondi’s “Rubbish House”," M/C Journal, 9(5). Retrieved echo date('d M. Y'); ?> from <http://journal.media-culture.org.au/0610/07-seale.php>.

The release of the film Fight Club (Dir. David Fincher, 1999) was met with an outpouring of contradictory reviews. From David Ansen’s [Newsweek] claim that “Fight Club is the most incendiary movie to come out of Hollywood in a long time” (Fight Club DVD insert) to LA Times’s Kenneth Turan who proclaimed Fight Club to be “…a witless mishmash of whiny, infantile philosophising and bone-crushing violence that actually thinks it’s saying something of significance” (Fight Club DVD insert), everyone, it seemed, needed to weigh in with their views. Whether you think the film is a piece of witless and excessive trash, or believe, as Fight Club novelist Chuck Palahniuk hopes “it would offer more people the idea that they could create their own lives outside the existing blueprint for happiness offered by society,” this is a film that people react strongly to (Fight Club DVD insert). Whether or not the film is successful in the new ‘blueprint’ area is debatable and one focus of this essay. It isn’t difficult to spot the focus of the film Fight Club. The title and the graphic, edgy trailers for the film leave no doubt in the viewer’s mind that this film is about fighting. But fighting what and why are the questions that unveil the deeper edge to the film, an edge that skirts the abyss of deep psychological schism: man’s alienation from man, society and self, and the position of the late twentieth century male whose gendered potentialities have become muted thanks to corporate cookie-cutter culture and the loss of a ‘hunter-gatherer’ role for men. In a nutshell, the film explores the psychic rift of the main character, unnamed for the film, but conventionally referred to as “Jack” (played by Ed Norton). Jack leads a life many late twentieth century males can identify with, a life without real grounding, focus or passion. It is the kind of life that has become a by-product of the “me” generation and corporate/consumer culture. Aside from Jack’s inability to find real satisfaction in his love life, friendships, job, or sense of self, he also suffers from an identity disorder. While there are few people who are unaware of the mind-numbing (and in some cases, audience-alienating) “twist” offered near the end of the film, it bears repeating that the compelling character of Tyler Durden (played by Brad Pitt) who shapes and influences the changes in Jack’s life is actually revealed near the end of the film as a manifestation of Jack’s alter ego. Jack and Tyler are the same person. The two conspire to start ‘Fight Club’, where men hit other men. Hard. The Club becomes an underground sensation, expanding to other communities and cities and eventually spawns the offshoot Project Mayhem whose goal it is to ultimately erase individual debt so everyone (all consumers) can start at zero. In order to manage this affair, several large buildings are slated for destruction by the Mayhem team. Of course no people will be in the buildings at the time, but all the records will be destroyed. This is the core of the film, but there are several other interesting sidelights that will become important to this discussion, including the lone female character Marla who becomes the love interest of Jack/Tyler, and the friend Bob, whom Jack meets during his insomniac foray into the seedy underworld of the self help meeting. The film itself seems to cry out for a psychoanalytic reading. Its thinly veiled references to Freudian concepts and subliminal tricks aside, it also makes the inner world of the protagonist its landscape and backdrop. In a film dominated by a psychological and psychical problem, psychoanalysis seems an excellent tool for delving more deeply into the symbols and attitudes of the piece. I have chosen both Kleinian object relations and Julia Kristeva’s understanding of abjection to help illuminate some issues in the film. Object relations helps to make clear both the divergence of personality and the emergence of a ‘repaired’ protagonist at the end of the film as Jack first creates and then destroys his alter ego. Kristeva initially explored abjection theory via literature in Powers of Horror (1982), but Barbara Creed’s Monstrous Feminine: Film, Feminism and Psychoanalysis (1993) opened wide the door for applications of the theory to film studies. Creed uses abjection to explore issues of gender in the horror film, focusing on the role and depiction of women as abject. Here, I have adapted some of her ideas and intend to explore the role of abjection in the male identification process. In this film fighting operates as both reality and metaphor, on both the physical and psychical levels, encompassing the internal and external fight within the mind and body of the protagonist. Jack’s main problem is a lack of concrete identity and self-realization. Numbed by his willing and eager participation in consumer culture and his tacit compliance with the gritty underworld of his job as an automotive ‘recall coordinator’, his life’s work is estimating the cost effectiveness of saving lives by calculating the cost of death. In Jack’s world, meaning is derived solely through the external—external products he consumes and collects. Jack’s consumer-based emasculation is expressed when he states, “Like so many others I had become a slave to the Ikea nesting instinct.” In this sentence he clarifies his disempowerment and feminisation in one swoop. Having few, if any, relationships with human beings, meaningful or otherwise, Jack never reaches a level of social maturity. His only solace comes from visiting anonymous help groups for the terminally ill. Although Jack is physically fine (aside from his insomnia) a part of him is clearly dying, as his sense of who he is in a postmodern culture is hopelessly mediated by advertisements that tell him what to be. In the absence of a father, Jack appears to have had no real role models. Made ‘soft’ by his mother, Jack exhibits a not so subtle misogyny that is illustrated through his relationship with fellow ‘tourist’ in the self-help circles, Marla Singer. Jack’s identity issues unfold via various conflicts, each of which is enmeshed in the club he starts that revolves around the physical pain of hand-to-hand, man-on-man combat. Jack’s conflicts with himself, others and society at large are all compressed within the theme and practice of fighting and the fight clubs he institutes. Fighting for Jack (and the others who join) seems the answer to life’s immediate problems. This essay looks deeply into Jack’s identity conflict, viewing it as a moment of psychic crisis in which Jack creates an alternate personality deeply steeped in and connected to the ‘abject’ in almost every way. Thus, Jack forces himself to confront the abject in himself and the world around him, dealing with abjection on several levels all with a view to expelling it to restore the ‘clean and proper’ boundaries necessary in the ‘whole’ self. Viewed though the lens of psychoanalysis, particularly Klein’s work on object relations and Kristeva’s work with abjection, allows a reading in which the film expresses the need for and accomplishment of a self-activated encounter with the abject in order to redraw ‘clean and proper’ boundaries of self. This film’s tag lines, ‘Mischief, Mayhem and Soap’—illustrate both the presence (Mischief, Mayhem) and function (Soap) of the abject—the interaction with the abject will lead to a ‘clean’ subject—a proper subject, a restored subject. Before continuing, a brief discussion of abjection and object relations and the ways in which they are utilized in this essay is essential here. One of Klein’s major propositions is that “the neonate brings into the world two main conflicting impulses: love and hate” (Mitchell 19). Each of these conflicting impulses must be dealt with, usually by either “bringing them together in order to modify the death drive along with the life drive or expelling the death drive into the outside world” (19). Along with this conflict arises the conflict of a primary relationship with the mother, which is seen as both satisfying and frustrating, and then later complicated with the addition of the father. The main conflicting love/hate binary is reflective of a number of ‘sets’ of dualities that surface when looking into the mother/child relationship. Besides love and hate, there is the ‘good’ and ‘bad’ mother, the mother as symbolic of both life and death, the symbolic (paternal) and semiotic (maternal), total oneness and total autonomy. The curious ‘split’ nature of the infant’s perception of the maternal figure recalls a kind of doppelganger, a doubling of the maternal (in positive and negative incarnations), that can be seen as abject. In the film, this informs the relationship between both Jack and Marla and Jack and Tyler, as I argue Tyler and Marla serve as parental substitutes at one part in the film. This is clarified in Jack’s statements about his relationship with the two of them: “My parents pulled this exact same act for years” and “I am six years old again, passing messages between parents.” This imaginary relationship allows Jack to re-experience some of his early identification processes, while effectively trading out the gender responsibilities to the point where Tyler symbolically takes the place of the ‘mother’ and Marla the place of the ‘father’. The result of this action is an excess of male gendered experiences in which Jack in crisis (emasculated) is surrounded by phalluses. Kristeva’s work with abjection is also important here. I am especially interested in her understanding of the mother/child relationship as connected with abjection, particularly the threat the mother represents to the child as wanting to return to a state of oneness. The abject functions in Fight Club as a means for the protagonist to re-configure his own autonomy. For Kristeva, the abject is that which is cast out in order that “I” may exist. It exists at the borders of the self and continually draws the subject into it. As the subject revolts and pulls away, its resistance cues the process of defining itself as separate, proper and autonomous. When the narrative of Jack’s life refuses to make sense to him, and his experiences seem like “a copy of a copy of a copy,” Jack turns inward for help. Kristeva says that the abject is “experienced at the peak of its strength when that subject, weary of fruitless attempts to identify with something on the outside, finds the impossible within” (5). Thus Jack ‘finds’ Tyler. The abject, [represented by Bob, Tyler and Marla in the film] is that which disturbs “identity, system, order. What does not respect borders, positions, rules” (Kristeva 4). As the abject is that which blurs boundaries borders and classification, the film itself is steeped in abject images and ideas. The discrete categories of inside/outside, asleep/awake, male/female, and self/other are continually troubled throughout the narrative. The two most confused binaries are male/female and self/other. As the film is about Jack’s own experience of emasculation it is not until the male/female gender issues are resolved that his self/other issues can be resolved. Through the re-ordering of gender he is able to take his place in society alongside Marla, finally viewed as not his mother or friend but lover. Jack Versus Himself: A Cult Of One Jack is able to re-vamp his personality through exposure to the abject and the replaying of certain key object relations moments in his childhood. He engages with this ‘inner child’ to reconnect with psychically difficult moments in which his ‘self’ emerged. Jack, however, twists the typical plot of maternal and paternal bonding in ways that speak to the underlying misogyny of the film and of late twentieth century society as well. While the story begins with both male and female characters in unnatural roles with unnatural and abject body parts, by the end of the film, these ‘abnormalities’ or abject objects are erased, ejected from the text so Jack is restored to the ‘safety’ of a compulsory heterosexuality. Bob, Tyler and Marla’s characters are three examples of gender twisting expressed in the film. In psychoanalytic literature, the child bonds first to the mother (via feeding from the breast and in-utero existence) and experiences a feeling of total oneness impossible to duplicate. Eventually the child seeks autonomy and breaks from the mother and her clinging ways with the help of the father and the phallus. So in basic terms, the female is abject, representing infantile regression and oneness, and the male represents taking the proper place in the symbolic order. When the female (mother) is denied, the male accepts his natural place in culture and society. However, in this film, Tyler (the male) is the abject presence in the text, that which threatens to consume and subsume the narrator’s personality. It is Marla, the phallic woman, who interposes herself in this dyad and becomes the correct choice for Jack, allowing him to proceed into ‘normal relations.’ Early in the film, Jack is unable to envision a female partner with whom he can open up and share, instead substituting Bob—and his doubly signified ‘bitch-tits’—as a locus of comfort. In Bob’s ample bosom, Jack finds the release he is looking for, though it is unnatural in more ways than one. The feminised Bob [testicular cancer patient] comforts and coddles Jack so much that he feels the same idyllic bliss experienced by the infant at the mother’s breast; Jack feels “lost in oblivion, dark and silent and complete.” That night he is able for the first time in months to sleep: “Babies don’t sleep this well.” This illustrates Jack’s longing for the safety and security of the mother, complicated by his inability to bond with a female, replaced with his deep need for identification with a male. Continuing the twist, it is Marla who foils Jack’s moment of infantile bliss: “She ruined everything” with her presence, Jack sneers. Jack’s regression to this infantile bliss with either man or woman would be perceived as abject, (disrupting system and order) but this particular regression is at least doubly abject because of Bob’s unnatural breasts and lack of testicles. Both Bob, and to some degree Tyler, offer abjection to Jack as a way of dealing with this complexities of autonomous living. While my argument is that Tyler takes the traditional ‘female’ role in the drama, as a figure (like Bob) who lures Jack into an unnatural oneness that must ultimately be rejected, it is true that even in his position as abject ‘female’ (mother), Tyler is overwhelmingly phallic. His ‘jobs’ consist of splicing shots of penises into films, urinating and masturbating into restaurant food and engaging in acrobatic sex with Marla. Since Marla, who occupies the position of father bringing Jack into society away from the influence of Tyler, is also coded phallic, Jack’s world is overwhelmingly symbolically male. This appears to be a response to the overwhelming physical presence of Jack’s mother of which Tyler comments, “We’re a generation of men raised by women. I am wondering if another woman is really the answer we need?” During this same scene, Jack clarifies his regressive dilemma: “I can’t get married, I am a thirty year old boy.” Thus while Tyler campaigns for a world without women, Jack must decide if this is the correct way to go. Immersion in the world of uber-maleness only seems to make his life worse. It is only after he ‘kills’ Tyler and accepts Marla as a partner that he can feel successful. In another help meeting, one of the guided meditations emphasizes his regression by asking him to go to his “cave” and locate his “power animal.” This early in the film, Jack can only envision his power animal as a rather silly penguin, which, although phallic to some extent, is undercut by the fact that it speaks with a child’s voice. In the next visualization of the ‘power animal’, the animal becomes Marla—clarifying her influence over Jack’s subconscious. The threat of Marla’s sexuality is on one level explored with Jack’s counterpart Tyler, the one who dares to go where Jack will not, but their encounters are not shown in a ‘natural’ or fully mature light. They are instead equated with childhood experimentation and regressive fantasies as Marla responds that she “hasn’t been fucked like that since grade school” and Tyler proclaims the relationship is mere “sportfucking.” It is Tyler who discovers Marla’s oversized dildo proudly displayed on a dresser, of which she states “Don’t worry its not a threat to you.” This phallicized Marla refers to herself as “infectious human waste,” clearly abject. Marla’s power must be muted before Jack can truly relate to her. This is illustrated in two separate ‘visions’ of sexual intercourse—one between Marla and Tyler early in the film in which Marla assumes the dominant position, and then later near the end of the film when the same encounter is replayed with Jack taking Tyler’s place, Marla now in the standard missionary position on her back: Proper. Jack’s struggle with self is played out via his relationship with Tyler (and Marla to some degree). Once Jack has been exposed to the various levels of abject behaviour offered by Tyler and Project Mayhem, he chooses to go it alone, no longer needing the double he himself created. After experiencing and rejecting the abject, Jack redraws his boundaries and cleanses his soul. Jack Versus Society—The Personal Is Political Jack’s personal struggle becomes political—and communal. Another attempt at forming identity, Fight Club is bound to fail because it offers not autonomy but a group identity substituted for an individual one. While Jack loathes his ‘single serving life’ before Fight Club, he must come to realize that a group identity brings more problems than solutions in an identity crisis. While the comfort of ‘oneness’ is alluring, it is also abject. As Jack is able to finally refuse the safely and oneness offered by Tyler’s existence, he must also deny the safety in numbers offered by Fight Club itself. The cult he creates swallows members whole, excreting them as the “all singing all dancing crap of the world.” They eat, drink and sleep Fight Club and eventually its ‘evolutionary’ offshoot, Project Mayhem. During his involvement with Fight Club and Project Mayhem, Jack is exposed to three levels of abjection including food loathing, bodily wastes, and the corpse, each of which threaten to draw him to the “place where meaning collapses” (Kristeva 2). Jack’s first experience involves Tyler’s (a)vocation as a waiter who urinates and probably masturbates into patrons’ food. This mingling of bodily wastes and nourishment represents the most elementary form of abjection: food loathing. While Jack appears amused at Tyler’s antics in the beginning, by the end of the film, he illustrates his movement closer to self-identification, by calling for “clean food, please” signalling his alliance with the clean and proper. Bodily wastes, the internal made visible, represent the most extended contact Jack has with the abject. These experiences, when what is properly outside ends up inside and vice versa, begin with bloody hand-to-hand combat, including Tyler’s vomiting of blood into the mouth of an unwilling Fight Club participant “Lou”, causing another witness to vomit as well. The physical aversion to abject images (blood, pus, excrement) is part of the redrawing of self—the abject is ejected –via nausea/vomiting. Kristeva explains: “I give birth to myself amid the violence of sobs, of vomit” (3). The images continue to pile up as Jack describes life in the Paper Street house: “What a shit hole.” The house slowly decomposes around them, leaking and mouldy, releasing its own special smell: the rot of a “warm stale refrigerator” mixed with the “fart smell of steam” from a nearby industrial plant. While at Paper Street, Tyler decides to make soap. Soap in itself is an agent of cleanliness, but in this context it is abject and defiled by being composed of human waste. In a deeply abject moment, Jack is accidentally covered in refuse that spills from a ripped bag full of human fat pilfered from a liposuction clinic. Even at this profoundly disturbing moment, Jack is unwilling to give up his associations with Tyler and Project Mayhem. It is only after his encounter with a corpse that he changes his tune. While Fight Club attempted to blur physical boundaries via hand-to-hand combat and exchange of blood and blows, Project Mayhem threatens the psychic boundaries of self, a deeper danger. While a loud speaker drones “we are all part of the same compost heap” and a fellow occupant reminds Jack “In project mayhem we have no names,” Jack realizes he is truly losing himself, not gaining strength. Mayhem’s goal of ‘oneness’, like the maternal and infant experience, is exposed via slogans like “you are not a beautiful and unique snowflake. You are the same decaying organic matter as everything else.” Tyler finally puts his cards on the table and asks Jack to “stop trying to control everything and just let go.” For Kristeva, “If dung signifies the other side of the border, the place where I am not and which permits me to be, the corpse, the most sickening of wastes, is a border that has encroached upon everything”(3). The corpse of Bob causes Jack to confront the boundaries of life and death, both spiritual and physical, as he opens his eyes to the damaging effects of the cult-like environment into which he has fallen. Jack’s momentary indecision morphs into action after Bob’s death becomes just one more mantra for the zombie-like Project Mayhemers to chant: “His name was Robert Paulson.” Jack’s internal and external struggles are compressed into one moment when he commits homo(sui)cide. Placing a gun in his mouth, he attempts to rid himself of Tyler forever, his final words to Tyler: “My eyes are open now”. At this point, Jack is psychically ready to take charge of his life and confidently eject the abject from the narrative of his life. He wants no more to do with Project Mayhem gang and is reunited with Marla with whom he finally appears ready to have a fully realized relationship. His masculinity and identity restoration are made blindingly apparent by the final splice in the film—the image of Marla and Jack hand in hand overlooking the new view out of the tower, spliced with the shot of a semi-erect penis—back to shot of Marla and Jack. The message is clear: Jack is a man, he has a woman, and he knows who he is because of it. While Fight Club novelist Palahniuk hopes the film offers options for life “outside the existing blueprint offered by society” (Fight Club DVD insert). On the other hand, it’s unclear how well the film pulls this off. On one hand, its lambasting of the numbing effects of blind and excessive consumerism seems well explored, it’s unclear what options really surface by the end of the film. Although many targeted buildings have been destroyed, through which the viewer can assume some or even most records of individual debt were erased, the building in which Marla and Jack stand (initially slated for destruction) remains. Perhaps this is meant to signify the impossibility of true financial equality in American society. But it seems to me that the more pressing issues are not the ones openly addressed in the film (that of money and consumerism) but rather the more internalised issues of self-actualisation, gender identity and contentment. In a postmodern space ripe for the redrawing and redefinition of gender stereotypes, this film carefully reinscribes not only compulsory heterosexuality but also the rigid boundaries of acceptable male and female behaviour. For this film, the safest route to repairing male identity and self-hood threatened by the emasculating practices of a consumer culture is a route back. Back to infantile and childhood fantasy. While it dances provocatively around the edges of accepting a man with ‘bitch tits’ and a woman with a dick, ultimately Bob is killed and Marla reclaimed by Jack in an ‘I’m ok you’re ok’ final scene: “Look at me Marla, I am really OK”. Jack’s immersion in an all male cult(ure) is eschewed for the comfort of real breasts. Works Cited Creed, Barbara. The Monstrous Feminine: Film, Feminism and Psychoanalysis. New York: Routledge, 1993. Fight Club. Dir. David Fincher. 1999. Fight Club DVD edition. Dir. David Fincher. 2000. Kristeva, Julia. Powers of Horror: An Essay On Abjection. New York: Columbia Press: 1982. Mitchell, Juliet. The Selected Melanie Klein. New York: The Free Press, 1986. Citation reference for this article Substitute your date of access for Dn Month Year etc... MLA Style Caldwell, Tracy M.. "Identity Making from Soap to Nuts" M/C: A Journal of Media and Culture 6.1 (2003). Dn Month Year < http://www.media-culture.org.au/0302/10-identitymaking.php>. APA Style Caldwell, T. M., (2003, Feb 26). Identity Making from Soap to Nuts. M/C: A Journal of Media and Culture, 6,(1). Retrieved Month Dn, Year, from http://www.media-culture.org.au/0302/10-identitymaking.html