|
[[চিত্র:Nucleus_drawing.svg|thumb|একটি পারমাণবিক নিউক্লিয়াসে দুই ধরনের নিউক্লিয়ন থাকে: [[প্রোটন]] (লাল) এবং [[নিউট্রন]] (নীল). ]]
[[রসায়ন]] ও [[পদার্থবিজ্ঞান|পদার্থবিদ্যায়]] পরমাণুর নিউক্লিয়াস গঠনের অন্যতম উপাদান হল নিউক্লিয়ন। প্রতিটি পারমাণবিক নিউক্লিয়াস এক বা একাধিক নিউক্লিয়ন দিয়ে গঠিত হয় এবং নিউক্লিয়াস এক বা একাধিক ইলেকট্রন দ্বারা পরিবেষ্টিত থাকে। নিউক্লিয়ন দুই প্রকার: [[নিউট্রন]] ও [[প্রোটন]]। এই [[আণবিক ভর সংখ্যা|ভর সংখ্যা]] ও নিউক্লিয়নের সংখ্যা একই। তাই বেশিরভাগ ক্ষেত্রে নিউক্লিয়ন ব্যবহার না করে [[আণবিক ভর সংখ্যা|ভর সংখ্যা]] হিসাবেই ব্যবহার করা হয়।
==বিস্তারিত বৈশিষ্ট্য ==
=== নিউক্লিয়ন ===
{| class="wikitable sortable" style="text-align:center; width:100%;"
|+ Nucleons (''[[Isospin|I]] = {{frac|1|2}}; [[strangeness|S]] = [[charm (quantum number)|C]] = [[bottomness|B]] = 0'')
|-
! Particle<br />name
! class="unsortable" | Symbol
! class="unsortable" | Quark<br />content
! [[Rest mass]] ([[electron volt|MeV]]/[[speed of light|c]]<sup>2</sup>)
! Rest Mass ([[atomic mass unit|u]])<sup>{{ref|nucleonmass|[a]}}</sup>
! ''[[Isospin|I]]<sub>3</sub>''
! ''[[Total angular momentum|J]]''<sup>''[[Parity (physics)|P]]''</sup>
! ''[[Electric charge|Q]]'' ([[elementary charge|e]])
! [[Magnetic moment]]
! [[Mean lifetime]] ([[second|s]])
! class="unsortable" | Commonly decays to
|-
| style="text-align:left;"| [[proton]]<ref name=PDGProton group="PDG">[http://pdg.lbl.gov/2010/listings/rpp2010-list-p.pdf Particle listings – {{SubatomicParticle|Proton}}]</ref>
| {{SubatomicParticle|Proton}} / {{SubatomicParticle|Proton+}} / {{SubatomicParticle|Nucleon+}}
| {{SubatomicParticle|link=yes|Up quark}}{{SubatomicParticle|Up quark}}{{SubatomicParticle|link=yes|Down quark}}
| {{sort|0938.272013|{{val|938.272013|0.000023}}}}
| {{sort|1.00727646688|{{val|1.00727646677|0.00000000010}}}}
| {{sort|0.5|+{{frac|1|2}}}}
| {{sort|0.5|{{frac|1|2}}}}<sup>+</sup>
| {{sort|1|+1}}
| {{sort|2.7|{{val|2.792847356|0.000000023}}}}
| {{sort|+10|Stable}}<sup>{{ref|protonlifetime|[b]}}</sup>
| Unobserved
|-
| style="text-align:left;"| [[neutron]]<ref name=PDGNeutron group="PDG">[http://pdg.lbl.gov/2010/listings/rpp2010-list-n.pdf Particle listings – {{SubatomicParticle|Neutron}}]</ref>
| {{SubatomicParticle|Neutron}} / {{SubatomicParticle|Neutron0}} / {{SubatomicParticle|Nucleon0}}
| {{SubatomicParticle|Up quark}}{{SubatomicParticle|Down quark}}{{SubatomicParticle|Down quark}}
| {{sort|0939.565346|{{val|939.565346|0.000023}}}}
| {{sort|1.00866491560|{{val|1.00866491597|0.00000000043}}}}
| {{sort|-0.5|-{{frac|1|2}}}}
| {{sort|0.5|{{frac|1|2}}}}<sup>+</sup>
| {{val|0}}
| {{sort|-1.9|{{val|-1.91304273|0.00000045}}}}
| {{sort|+2|{{val|8.857|0.008|e=+2}}}}<sup>{{ref|neutronlifetime|[c]}}</sup>
| {{nowrap|{{SubatomicParticle|link=yes|Proton}} + {{SubatomicParticle|link=yes|Electron}} + {{SubatomicParticle|link=yes|Electron antineutrino}}}}
|-
| style="text-align:left;"| [[antiproton]]
| {{SubatomicParticle|Antiproton}} / {{PhysicsParticle|p|TR=−}} / {{PhysicsParticle|N|TR=−}}
| {{SubatomicParticle|Up antiquark}}{{SubatomicParticle|Up antiquark}}{{SubatomicParticle|Down antiquark}}
| {{sort|0938.272013|{{val|938.272013|0.000023}}}}
| {{sort|1.00727646688|{{val|1.00727646677|0.00000000010}}}}
| {{sort|-0.5|-{{frac|1|2}}}}
| {{sort|0.5|{{frac|1|2}}}}<sup>+</sup>
| {{sort|-1|−1}}
| {{sort|-2.7|{{val|-2.793|0.006}}}}
| {{sort|+10|Stable}}<sup>{{ref|protonlifetime|[b]}}</sup>
| Unobserved
|-
| style="text-align:left;"| [[antineutron]]
| {{SubatomicParticle|Antineutron}} / {{SubatomicParticle|Antineutron0}} / {{SubatomicParticle|Antinucleon0}}
| {{SubatomicParticle|Up antiquark}}{{SubatomicParticle|Down antiquark}}{{SubatomicParticle|Down antiquark}}
| {{sort|0939.565346|{{val|939.485|0.051}}}}
| {{sort|1.00866491560|{{val|1.00866491597|0.00000000043}}}}
| {{sort|0.5|+{{frac|1|2}}}}
| {{sort|0.5|{{frac|1|2}}}}<sup>+</sup>
| {{val|0}}
| ?
| {{sort|+2|{{val|8.857|0.008|e=+2}}}}<sup>{{ref|neutronlifetime|[c]}}</sup>
| {{nowrap|{{SubatomicParticle|link=yes|Antiproton}} + {{SubatomicParticle|link=yes|Positron}} + {{SubatomicParticle|link=yes|Electron neutrino}}}}
|}
{| class="wikitable"
|+ Proton-antiproton CPT invariance tests
! Test
! Formula
! RPG Result<ref group="PDG" name="PDGProton">[http://pdg.lbl.gov/2010/listings/rpp2010-list-p.pdf Particle listings – p]</ref>
|-
| [[ভর|Mass]]
|<math>\frac{|m_p-m_\bar{p}|}{m_p}</math>
|< {{Val|2|e=-9}}
|-
| Charge-to-mass ratio
|<math>\frac{|\frac{q_\bar{p}}{m_\bar{p}}|}{(\frac{q_p}{m_p})}</math>
|{{Val|0.99999999991|0.00000000009}}
|-
| Charge-to-mass-to-mass ratio
|<math>\frac{|\frac{q_\bar{p}}{m_\bar{p}}| - \frac{q_p}{m_p}}{\frac{q_p}{m_p}}</math>
|{{Val|-9|9|e=-11}}
|-
| Charge
|<math>\frac{|q_p+q_\bar{p}|}{e}</math>
|< {{Val|2|e=-9}}
|-
| Electron charge
|<math>\frac{|q_p+q_e|}{e}</math>
|<{{Val|1|e=-21}}
|-
| Magnetic moment
|<math>\frac{|\mu_p+\mu_\bar{p}|}{\mu_p}</math>
|{{Val|-0.1|2.1|e=-3}}
|}
{| class="wikitable sortable" style="text-align:center; width:100%;"
|+ Nucleon resonances (I = {{Frac|1|2}})
! Symbol
! ''J''<sup>''P''</sup>
! PDG [[স্থির ভর|mass]] average<br>
([[ইলেক্ট্রন-ভোল্ট|MeV]]/[[আলোর গতিবেগ|c]]<sup>2</sup>)
! Full Width<br>
(MeV/c<sup>2</sup>)
! Pole Position<br>
(Real Part)
! Pole Position<br>
(−2 × Imaginary Part)
! class="unsortable" |Common decays<br>
(Γ<sub>i</sub> /Γ > 50%)
|- style="height:40px"
| N(939) P<sub>11</sub><br>
<ref group="PDG" name="PDGN939">[http://pdg.lbl.gov/2011/reviews/rpp2011-rev-n-delta-resonances.pdf Particle listings — Note on N and Delta Resonances]</ref>†
| 0.5 !<span class="sorttext"><span class="frac nowrap"><sup>1</sup>⁄<sub>2</sub></span></span><sup>+</sup>
| 939
| †
| †
| †
| †
|- style="height:40px"
| N(1440) P<sub>11</sub><br>
<ref group="PDG" name="PDGN1440">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-1440-P11.pdf Particle listings — N(1440)]</ref><br>
aka the Roper resonance
| 0.5 !<span class="sorttext"><span class="frac nowrap"><sup>1</sup>⁄<sub>2</sub></span></span><sup>+</sup>
| 1440<br>
(1420–1470)
| 300<br>
(200–450)
| 1365<br>
(1350–1380)
| 190<br>
(160–220)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}}}}
|- style="height:40px"
| N(1520) D<sub>13</sub><br>
<ref group="PDG" name="PDGN1520">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-1520-D13.pdf Particle listings — N(1520)]</ref>
| 1.5 !<span class="sorttext"><span class="frac nowrap"><sup>3</sup>⁄<sub>2</sub></span></span><sup>−</sup>
| 1520<br>
(1515–1525)
| 115<br>
(100–125)
| 1510<br>
(1505–1515)
| 110<br>
(105–120)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}}}}
|- style="height:40px"
| N(1535) S<sub>11</sub><br>
<ref group="PDG" name="PDGN1535">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-1535-S11.pdf Particle listings — N(1535)]</ref>
| 0.5 !<span class="sorttext"><span class="frac nowrap"><sup>1</sup>⁄<sub>2</sub></span></span><sup>−</sup>
| 1535<br>
(1525–1545)
| 150<br>
(125–175)
| 1510<br>
1490 — 1530)
| 170<br>
(90–250)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}} or}}<br>
{{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Eta}}}}
|- style="height:40px"
| N(1650) S<sub>11</sub><br>
<ref group="PDG" name="PDGN1650">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-1650-S11.pdf Particle listings — N(1650)]</ref>
| 0.5 !<span class="sorttext"><span class="frac nowrap"><sup>1</sup>⁄<sub>2</sub></span></span><sup>−</sup>
| 1650<br>
(1645–1670)
| 165<br>
(145–185)
| 1665<br>
(1640–1670)
| 165<br>
(150–180)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}}}}
|- style="height:40px"
| N(1675) D<sub>15</sub><br>
<ref group="PDG" name="PDGN1675">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-1675-D15.pdf Particle listings — N(1675)]</ref>
| 2.5 !<span class="sorttext"><span class="frac nowrap"><sup>5</sup>⁄<sub>2</sub></span></span><sup>−</sup>
| 1675<br>
(1670–1680)
| 150<br>
(135–165)
| 1660<br>
(1655–1665)
| 135<br>
(125–150)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}} + {{SubatomicParticle|link=yes|Pion}} or}}<br>
{{Nowrap|{{SubatomicParticle|link=yes|Delta}} + {{SubatomicParticle|link=yes|Pion}}}}
|- style="height:40px"
| N(1680) F<sub>15</sub><br>
<ref group="PDG" name="PDGN1680">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-1680-F15.pdf Particle listings — N(1680)]</ref>
| 2.5 !<span class="sorttext"><span class="frac nowrap"><sup>5</sup>⁄<sub>2</sub></span></span><sup>+</sup>
| 1685<br>
(1680–1690)
| 130<br>
(120–140)
| 1675<br>
(1665–1680)
| 120<br>
(110–135)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}}}}
|- style="height:40px"
| N(1700) D<sub>13</sub><br>
<ref group="PDG" name="PDGN1700">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-1700-D13.pdf Particle listings — N(1700)]</ref>
| 1.5 !<span class="sorttext"><span class="frac nowrap"><sup>3</sup>⁄<sub>2</sub></span></span><sup>−</sup>
| 1700<br>
(1650–1750)
| 100<br>
(50–150)
| 1680<br>
(1630–1730)
| 100<br>
(50–150)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}} + {{SubatomicParticle|link=yes|Pion}}}}
|- style="height:40px"
| N(1710) P<sub>11</sub><br>
<ref group="PDG" name="PDGN1710">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-1710-P11.pdf Particle listings — N(1710)]</ref>
| 0.5 !<span class="sorttext"><span class="frac nowrap"><sup>1</sup>⁄<sub>2</sub></span></span><sup>+</sup>
| 1710<br>
(1680–1740)
| 100<br>
(50–250)
| 1720<br>
(1670–1770)
| 230<br>
(80–380)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}} + {{SubatomicParticle|link=yes|Pion}}}}
|- style="height:40px"
| N(1720) P<sub>13</sub><br>
<ref group="PDG" name="PDGN1720">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-1720-P13.pdf Particle listings — N(1720)]</ref>
| 1.5 !<span class="sorttext"><span class="frac nowrap"><sup>3</sup>⁄<sub>2</sub></span></span><sup>+</sup>
| 1720<br>
(1700–1750)
| 200<br>
(150–300)
| 1675<br>
(1660–1690)
| 115–275
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}} + {{SubatomicParticle|link=yes|Pion}} or}}<br>
{{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Rho}}}}
|- style="height:40px"
| N(2190) G<sub>17</sub><br>
<ref group="PDG" name="PDGN2190">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-2190-G17.pdf Particle listings — N(2190)]</ref>
| 3.5 !<span class="sorttext"><span class="frac nowrap"><sup>7</sup>⁄<sub>2</sub></span></span><sup>−</sup>
| 2190<br>
(2100–2200)
| 500<br>
(300–700)
| 2075<br>
(2050–2100)
| 450<br>
(400–520)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}} (10—20%)}}
|- style="height:40px"
| N(2220) H<sub>19</sub><br>
<ref group="PDG" name="PDGN2220">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-2220-H19.pdf Particle listings — N(2220)]</ref>
| 4.5 !<span class="sorttext"><span class="frac nowrap"><sup>9</sup>⁄<sub>2</sub></span></span><sup>+</sup>
| 2250<br>
(2200–2300)
| 400<br>
(350–500)
| 2170<br>
(2130–2200)
| 480<br>
(400–560)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}} (10—20%)}}
|- style="height:40px"
| N(2250) G<sub>19</sub><br>
<ref group="PDG" name="PDGN2250">[http://pdg.lbl.gov/2011/listings/rpp2011-list-N-2250-G19.pdf Particle listings — N(2250)]</ref>
| 4.5 !<span class="sorttext"><span class="frac nowrap"><sup>9</sup>⁄<sub>2</sub></span></span><sup>−</sup>
| 2250<br>
(2200–2350)
| 500<br>
(230–800)
| 2200<br>
(2150–2250)
| 450<br>
(350–550)
| {{Nowrap|{{SubatomicParticle|link=yes|Nucleon}} + {{SubatomicParticle|link=yes|Pion}} (5—15%)}}
|}
== References ==
| 