12 results on '"Cross section measurement"'
Search Results
2. Proton-induced reactions for 47Sc (and 46Sc) production: new nuclear cross section measurements on enriched titanium targets
- Author
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Pupillo, Gaia, De Dominicis, Lucia, Cisternino, Sara, Esposito, Juan, Campostrini, Matteo, Rigato, Valentino, Haddad, Ferid, Nigron, Etienne, and Mou, Liliana
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- 2024
- Full Text
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3. Recent results and future perspectives with solid targets at LUNA.
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Ananna, Chemseddine, Barbieri, Lucia, Boeltzig, Axel, Campostrini, Matteo, Casaburo, Fausto, Ciani, Giovanni Francesco, Compagnucci, Alessandro, Gesuè, Riccardo Maria, Marsh, Jordan, Masha, Eliana, Mercogliano, Daniela, Rapagnani, David, Robb, Duncan, Sidhu, Ragandeep Singh, and Skowronski, Jakub
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NUCLEAR reactions , *ION beams , *SOLIDS , *STELLAR evolution - Abstract
The stellar evolution and chemical make-up of the Universe are determined by nuclear reactions occurring in a wide variety of stellar sites. Precise determinations of the cross sections of these reactions are crucial for the calculation of reaction rates and for the development of stellar evolution models. The Laboratory for Underground Nuclear Astrophysics (LUNA) collaboration has been at the forefront of the direct measurement of nuclear reactions at the low energies of astrophysical interest for the last 35 years. The many significant results achieved at LUNA have been made possible due to the low background conditions uniquely available thanks to its location deep underground at the Laboratori Nazionali del Gran Sasso. Another key aspect of these successes is due to the experience of the LUNA collaboration in the production and characterization of a variety of solid targets used in reaction measurements. In this review, the main production techniques of solid targets are described, as well as the common methods adopted for target degradation monitoring. We also present the results of recent measurements using these targets and the future plans of the LUNA collaboration for measurements using solid targets at the LUNA400 kV and the new Ion Beam Facility (IBF) 3.5 MV are also presented. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Recent results and future perspectives with solid targets at LUNA
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Chemseddine Ananna, Lucia Barbieri, Axel Boeltzig, Matteo Campostrini, Fausto Casaburo, Giovanni Francesco Ciani, Alessandro Compagnucci, Riccardo Maria Gesuè, Jordan Marsh, Eliana Masha, Daniela Mercogliano, David Rapagnani, Duncan Robb, Ragandeep Singh Sidhu, and Jakub Skowronski
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solid target ,evaporation ,sputtering ,cross section measurement ,nuclear astrophysics ,Astronomy ,QB1-991 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
The stellar evolution and chemical make-up of the Universe are determined by nuclear reactions occurring in a wide variety of stellar sites. Precise determinations of the cross sections of these reactions are crucial for the calculation of reaction rates and for the development of stellar evolution models. The Laboratory for Underground Nuclear Astrophysics (LUNA) collaboration has been at the forefront of the direct measurement of nuclear reactions at the low energies of astrophysical interest for the last 35 years. The many significant results achieved at LUNA have been made possible due to the low background conditions uniquely available thanks to its location deep underground at the Laboratori Nazionali del Gran Sasso. Another key aspect of these successes is due to the experience of the LUNA collaboration in the production and characterization of a variety of solid targets used in reaction measurements. In this review, the main production techniques of solid targets are described, as well as the common methods adopted for target degradation monitoring. We also present the results of recent measurements using these targets and the future plans of the LUNA collaboration for measurements using solid targets at the LUNA400 kV and the new Ion Beam Facility (IBF) 3.5 MV are also presented.
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- 2024
- Full Text
- View/download PDF
5. Ion beam activation of natCu, natTi, natNi and measurement of product formation cross sections at low energy (<10 MeV).
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Anwer, Mahwish, Naz, Anam, Ahmad, Ishaq, Usman, Muhammad, Hussain, Javed, Ilyas, Syed Zafar, and Shahid, Muhammad
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ION beams ,GAMMA ray spectroscopy ,COPPER-titanium alloys ,RADIOISOTOPES - Abstract
In this study we investigated the production cross sections of
nat Cu(p, x)63,65 Zn,nat Ti(p, x)48 V,nat Ni(p, x)55 Co,61 Cu andnat Cu(α, x)66,67,68 Ga,nat Ti(α, x)49,51 Cr,nat Ni(α, x)63,65 Zn reactions in the low energy range using the foil activation technique. The samples were activated in vacuum at 5 MV tandem (Pelletron) accelerator installed at National Centre for Physics (NCP), Islamabad, Pakistan. The reaction products were identified with the help of off-line gamma ray spectroscopy system connected with Genie 2000 software. The data analysis revealed the production of different radioisotopes that have valuable importance in monitoring charged-particle beams and medical applications. The measured results were verified by comparing them with earlier evaluated data as well as with the theoretical values given in the TENDL-library based on TALYS-1.9 code calculations. [ABSTRACT FROM AUTHOR]- Published
- 2022
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6. Production of 203Pb from enriched 205Tl using deuteron beams.
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Sounalet, Thomas, Guertin, Arnaud, Haddad, Ferid, Kamalakannan, Keerthana, and Nigron, Etienne
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DEUTERON reactions , *NUCLEAR reactions , *MERCURY isotopes , *NUCLEAR medicine , *POLLUTANTS , *DATABASES , *THALLIUM - Abstract
Lead-203 is a SPECT emitter that can be used in theranostic applications as an imaging counterpart of lead-212 which is intended to be used for alpha therapy as lead-212/bismuth-212 in-vivo generator. In our study, we explore the production of lead-203 using enriched thallium-205 target irradiated by a deuteron beam. Excitation functions of deuteron induced reactions leading to the formation of 204m,203m2+m1+g,202m,201m+gPb, 202Tl and 203m+gHg isotopes were determined experimentally in the energy range from 21 MeV to 34 MeV. Cross sections were measured using the stacked foils technique and a set of two monitor foils, natNi and natTi for beam intensity evaluation. The experimental excitation functions of the investigated reactions were compared with the published data and also with the TENDL-2021 nuclear database. From our experimental data, we calculated lead-203 thick target yield in the energy range between 30 MeV and 32.5 MeV to be 56.7 MBq/μAh ±6.1 MBq/μAh. This value is compatible with large batch production showing that deuteron beams can be used for a routine production process. However, special attention must be paid to 203Hg and other lead contaminants. • Deuteron induced reactions on thallium enriched to 205 (205Tl) up to 34 MeV. • Target preparation of 205Tl using the electrodeposition technique. • Stacked foil irradiation. • Production of 203Pb for nuclear medicine applications. • Comparison of thick target yields between proton and deuteron irradiation. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Fission cross-section measurements for the 238U(n,f)97m+gNb, 238U(n,f)133gTe and 238U(n,f)130gSb reactions induced by D-T neutrons.
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Han, Yafei, Qiao, Yujie, Li, Zhonglin, Han, Xueyan, Wang, Qiang, Fang, Kaihong, and Zhang, Shuo
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NEUTRON temperature , *NEUTRONS , *NEUTRON flux , *EXCITED states , *NEUTRON capture , *FISSION products - Abstract
In this study, we conducted measurements of the independent fission cross-sections of 238U(n, f)97m+gNb, 238U(n, f)133gTe reactions and the cumulative cross section of 238U(n, f)130gSb reactions induced by neutron at energies around 14 MeV, i.e. , 14.1 ± 0.3, 14.5 ± 0.3 and 14.7 ± 0.3 MeV. The measurement results were obtained by the neutron activation method in combination with off-line γ-ray spectrometry techniques. The neutron flux was monitored on line by the accompanying α-particle from T(d, n)4He reaction, and the neutron energies were determined by the cross-section ratio of 90Zr(n, 2n)8+gZr to 93Nb(n, 2n)92mNb reactions. The independent fission cross-sections of the fission reactions were obtained by subtracting the influence of precursor nuclei or excited states. The obtained results are as follows: for 238U(n, f)97m+gNb, the independent cross sections are 1.0 ± 0.89, 0.98 ± 0.85 and 0.78 ± 0.70 mb at the specified neutron energy points. For 238U(n, f)133gTe, the independent fission cross-sections are 26.8 ± 2.8, 27.7 ± 2.9 and 20.5 ± 2.3 mb, respectively, at the same neutron energy points. As for 238U(n, f)130gSb, the obtained cumulative fission cross-sections are 5.35 ± 0.58, 5.05 ± 0.53 and 4.03 ± 0.44 mb, respectively, at the specified neutron energy points. • Neutron-induced fission cross sections of 238U was measure for production 97m+gNb, 133gTe, and 130gSb using D-T neutrons. • The method used were neutron activation and off-line gamma-ray spectrometry. • The neutron energies used for the measurement of reaction cross section are 14.1 ± 0.3, 14.5 ± 0.3 and 14.7 ± 0.3 MeV. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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8. Measurement of dosimetrical cross sections with 14.05 MeV neutrons from compact neutron generator.
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Kostal, Michal, Czakoj, Tomáš, Alexa, Petr, Šimon, Jan, Zmeškal, Marek, Schulc, Martin, Krechlerová, Alena, Peltán, Tomáš, Mravec, Filip, Cvachovec, František, Rypar, Vojtěch, Uhlář, Radim, Harkut, Ondřej, and Matěj, Zdeněk
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NEUTRON generators , *NEUTRONS , *DIFFERENTIAL cross sections , *NEUTRON flux , *NEUTRON emission , *DATA libraries - Abstract
• Measurement of reaction rates in compact DT generator. • Calculation of neutron flux in targets around compact DT generator. • Determination of DD neutrons in compact DT generator. • Testing of IRDFF-II cross sections in 14.05 MeV neutrons. This paper deals with the measurement of the differential dosimetry cross sections using a small compact D-T neutron generator with 14.05 ± 0.08 MeV neutron emission (1 × 108 n/s into 4π). In spite of low neutron flux, it is possible to get measurable gamma-ray activities by irradiating a larger amount of target material placed in close geometry. The experimentally determined cross sections are in good agreement with the cross sections in the IRDFF-II dosimetry library. The comparison with other nuclear data libraries was performed as well. It is worth noting that the mean standard deviation in IRDFF-II library is about 4 %, while in the case of other data libraries they are from 5.5 % to 7.5 %. This result can be understood as a validation of IRDFF-II using 14.05 MeV neutrons and also a confirmation of the applicability of small compact generators in the measurement of activation cross sections. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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9. Producción de dos bosones W+W− en colisiones protón-protón a una energía de centro de masas de √ s = 13 TeV con el detector CMS del LHC
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Fernández Manteca, Pedro José, Calderón Tazón, Alicia, Vilar Cortabitarte, Rocío, and Universidad de Cantabria
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CMS experiment ,Cross section measurement ,W+W- boson pair ,Deep learning ,Highly energetic muons ,Higgs oscuro ,Aprendizaje automático profundo ,Muones altamente energéticos ,Dark matter ,LHC ,Medida de la sección eficaz ,Materia oscura ,Experimento CMS ,Par de bosones W+W ,Dark Higgs - Abstract
RESUMEN Se presenta la medida de la sección eficaz de producción de un par de bosones W+W- en colisiones protón-protón a una energía de centro de masas de 13 TeV. Los datos analizados en este estudio han sido recogidos por el detector CMS del LHC, y se corresponden con una luminosidad integrada de 35.9 fb-¹. Los eventos candidatos se seleccionan requiriendo dos leptones con carga opuesta. Se mide una sección eficaz de producción total de 117.6 ± 6.8 pb, que acuerda bien con la predicción teórica. También se hacen medidas de las secciones eficaces fiduciales y diferenciales, que acuerdan bien con las predicciones teóricas. Finalmente, se obtienen límites en los operadores de dimensión-6 en el contexto de la teoría de campo efectivo. Este análisis proporciona algunos de los límites más fuertes en dichos operadores comparando con resultados previos. Se realiza una búsqueda de materia oscura en colisiones protón-protón a una energía de centro de masa de 13 TeV usando eventos con un par de bosones W+W- y una gran cantidad faltante de momento transverso. Los datos usados en este estudio han sido recogidos por el detector CMS del LHC, y se corresponden con una luminosidad integrada de 137 fb-¹. Los eventos candidatos se seleccionan requiriendo dos leptones con carga opuesta. No se observa ningún exceso significativo de los datos sobre las predicciones del Modelo Estándar, por lo que se obtienen límites en la producción de materia oscura en el contexto del modelo simplificado de Higgs oscuro, con una masa para el bosón de Higgs oscuro por encima de la masa umbral del par W+W-. Los resultados presentados se corresponden con la primera medida realizada por el experimento CMS usando esta nueva interpretación. Se aplican técnicas de aprendizaje automático profundo para estimar el momento transverso de muones altamente energéticos en el detector CMS. El objetivo principal de estos estudios es mejorar los resultados del procedimiento utilizado actualmente, y de ser así, considerar incluir este tipo de metodologías en la futura toma de datos del experimento. Los resultados preliminares, basados en simulación, muestran una mejora de aproximadamente un 25% en la resolución de la asignación de momento transverso para muones con with 1500 < pT < 2500 GeV y |η| < 0.9. ABSTRACT A measurement of the W+W- boson pair production cross section in proton-proton collisions at a center-of-mass energy of 13 TeV is presented. The data used in this study are collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 35.9 fb-¹. The W+W- candidate events are selected by requiring two oppositely charged leptons. The total W+W- production cross section measurement has been 117.6 ± 6.8 pb, which agrees well with the theoretical prediction. Fiducial cross sections and differential cross sections are also reported, which also agree well with the theoretical prediction. Finally, constraints on the dimension-6 operators in the context of an effective field theory are derived. This analysis provides some of the strongest constraints compared with previous results. A search for dark matter in proton-proton collisions at a center-of-mass energy of 13 TeV is performed using events with a W+W- boson pair and large missing transverse momentum. The data used in this study are collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb-¹. The W+W- candidate events are selected by requiring two oppositely charged leptons. No significant excess over the expected Standard Model prediction is observed. Limits are set on dark matter production in the context of the dark Higgs simplified model, with a dark Higgs mass above the W+W- pair mass threshold. The results presented correspond to the first measurement carried out in the CMS experiment using this novel interpretation. Deep learning techniques are applied to estimate the transverse momentum of highly energetic muons in the CMS detector. The main goal of these studies is to improve the results of the current procedure, and if so, consider including these types of methodologies in the future data taking of the experiment. The preliminary results obtained, based on simulation, show an improvement of about 25% in the resolution of the transverse momentum for muons with 1500 < pT < 2500 GeV and |η| < 0.9.
- Published
- 2022
10. Medida de la sección eficaz de producción de dos bosones W con el experimento CMS
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Desiré Valdor, Paula, Calderón Tazón, Alicia, and Universidad de Cantabria
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W+W− production ,CMS experiment ,Likelihood fit ,Boosted Decision Tree ,Cross section measurement ,Ajuste de máxima verosimilitud ,Medida de la sección eficaz ,Producción de bosones W+W− ,Experimento CMS - Abstract
RESUMEN: El objetivo de este trabajo es medir con la máxima precisión posible la sección eficaz de producción de un par de bosones W en colisiones protón-protón a una energía de centro de masas de √s = 13 TeV. Para ello, se han utilizado datos recogidos por el experimento Compact Muon Soleniod (CMS) y una luminosidad total de L = 36.3 fb−1. Esta medida es una prueba directa de las predicciones del modelo estándar para la interacción electrodébil, además de ser útil para el estudio del bosón de Higgs decayendo a dos bosones W. Para ello, se han estudiado eventos en los que cada bosón W decae a un leptón y a un neutrino, por lo que se espera encontrar dos leptones y energía transversa faltante en el estado final. En concreto, solo se han considerado los eventos con dos leptones de distinto sabor, electrones o muones, y de carga contraria. El análisis se ha realizado seleccionando eventos con 0, 1 y 2 jets de manera independiente y se ha basado en encontrar una región lo más pura posible en procesos de la señal que se quiere estudiar, utilizando para ello el poder discriminatorio de ciertas variables cinemáticas. Una vez definida esta región, se ha procedido a realizar una primera medida de la sección eficaz de producción. Con el objetivo de mejorar la precisión de la medida, se ha procedido a medir dicha sección eficaz a partir del ajuste a ciertas distribuciones de las variables estudiadas. Por último, en el caso particular de los eventos con 2 jets, se ha necesitado buscar un método de mejora de esta medida, para lo cual se han utilizado técnicas de aprendizaje automático, en concreto un conjunto de árboles de decisión (BDT) capaces de mejorar la selección de eventos. Específicamente, el algoritmo utilizado ha sido entrenado para diferenciar entre fondo y señal. Los resultados obtenidos para los procesos con 0 y 1 jet son coherentes con las predicciones del modelo estándar para todas las estrategias utilizadas. En el caso de los eventos donde se requerían 2 jet, los resultados más precisos han sido los obtenidos al aplicar el BDT, siendo compatibles con el modelo estándar. ABSTRACT: The aim of this work is to measure with the highest possible precision the production cross section of two opposite charged W bosons in proton-proton collisions at a center of mass energy of √ s = 13 TeV, by using data collected by the Compact Muon Solenoid (CMS) experiment corresponding to a total luminosity of L = 36.3 fb−1. This measurement is a direct test of the predictions of the Standard Model (SM) in electroweak interaction, as well as being an important process in the study of Higgs boson decaying to two W bosons. In this work, it is considered that each of the W bosons decays to a lepton and a neutrino, so it is expected to find two leptons with different charge (electrons or muons) and missing transverse energy in the final signature. In particular, only events with different-flavored leptons have been considered. The analysis has been performed independently for processes with 0, 1 and 2 jets and it has been based on searching for a region which magnifies the signal over the backgrounds by using the discriminating power of certain kinematic variables. Once that region was defined, a first measurement of the production cross section was obtained. Then, a binned likelihood fit has been performed to certain variables, providing another measurement of the cross section. Finally, in the events with 2 jets, it was necessary to search for a method that improved the result. Techniques of machine learning able to improve the selection of events have been used for this purpose, obtaining another different cross section measurement. Specifically, the algorithm used has been a set of decision trees (BDT) trained to differentiate signal from background. In the processes in which 0 and 1 jets were required, the measured cross section values for each of the different strategies used are all in agreement with the SM predictions. In the 2-jet requirement, the most precise value of the cross section came from using a BDT, providing a measurement compatible with the SM. Grado en Física
- Published
- 2022
11. Reconstruction of gamma-ray source activity in a multiple samples set-up.
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Sękowski, P., Saworska, G., Skwira-Chalot, I., Spyra, A., Szcześniak, W., Matulewicz, T., Horwacik, T., and Swakoń, J.
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PHOTON detectors , *KINETIC energy , *GAMMA ray spectrometry , *PROTON beams , *PHOTONS , *DETECTORS - Abstract
When numerous radioactive samples irradiated simultaneously have to be measured using a single photon detector, the resulting energy spectrum comprises not only the yield from the source closest to the detector but also from all other sources. This case is particularly important when the sources are placed in a set-up exchanging them in an automated manner. In order to obtain relevant data for each source, correction procedures were developed and tested via Monte-Carlo simulations and with radioactive sources, in a set-up with up to 16 samples placed on a rotating wheel. In a test experiment, the cross-section of 12C(p, X)11C (X = d or p n) was determined using a stack of 15 carbon targets irradiated with a proton beam of initial 58 MeV kinetic energy. The 11C activity of simultaneously irradiated targets was measured (through 511 keV photons) and reconstructed using the developed correction procedures. The results of cross-section measurements are in agreement with the previous experiments, supporting the correctness of the reconstruction procedure. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
12. Electrochemical co-deposition of Ni–Gd2O3 for composite thin targets preparation: Production of 155Tb as a case study.
- Author
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Wang, Yizheng, Sounalet, Thomas, Guertin, Arnaud, Haddad, Férid, Michel, Nathalie, and Nigron, Etienne
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NUCLEAR cross sections , *CYCLOTRONS , *GADOLINIUM , *ALKALINE solutions , *TERBIUM , *NUCLEAR medicine - Abstract
In the last years, 155Tb has attracted enormous interest due to its potential role in theranostics in nuclear medicine. To estimate its production yield, the aim of this study was to develop a method to prepare thin Gd-enriched-containing targets aimed at the 155Gd(d, 2n)155Tb nuclear cross section measurement. To this end, the electrochemical co-deposition method has been chosen to manufacture Ni–Gd 2 O 3 composite targets. Several process parameters that have an impact on the deposit quality, have been investigated to increase the incorporation of Gd mass (up to 3 mg). To validate the concept, seven targets made by natural Gd were irradiated with deuteron beams at the GIP ARRONAX facility cyclotron, with an energy range ranging from 8 MeV to 30 MeV to extract the cross section values by using the stacked-foils method. Results obtained turned out to have great consistency with existing published data thus validating the proposed method. Therefore, an alternative target manufacturing concept aimed at cross section measurement is presented in this work. • Terbium cross section of the deuteron-induced reaction on natural gadolinium. • Manufacturing gadolinium-nickel composite targets by electrodeposition. • Incorporation of gadolinium in alkaline aqueous solution. • Target design for the production of terbium from enriched gadolinium. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
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