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CORRECTED FOR ACCEPTANCE.

The cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ integrated over each $\sqrt{\tau}$-$x_F$ cell as a function of $x_F$ for $\sqrt{\tau}$ = 0.30-0.33. The $\Upsilon$ region has been excluded. The integrated luminosity is $L = (8.58 \pm 0.53)\times 10^{37}$ [cm$^2$/W nucleus]$^{-1}$. Note that these data have been re-analysed by the NA10 experimenters using a better estimate of Fermi motion effects (see Tables 11-19 of this record).

The cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ integrated over each $\sqrt{\tau}$-$x_F$ cell as a function of $x_F$ for $\sqrt{\tau}$ = 0.33-0.36. The $\Upsilon$ region has been excluded. The integrated luminosity is $L = (8.58 \pm 0.53)\times 10^{37}$ [cm$^2$/W nucleus]$^{-1}$. Note that these data have been re-analysed by the NA10 experimenters using a better estimate of Fermi motion effects (see Tables 11-19 of this record).

The cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ integrated over each $\sqrt{\tau}$-$x_F$ cell as a function of $x_F$ for $\sqrt{\tau}$ = 0.36-0.39. The $\Upsilon$ region has been excluded. The integrated luminosity is $L = (8.58 \pm 0.53)\times 10^{37}$ [cm$^2$/W nucleus]$^{-1}$. Note that these data have been re-analysed by the NA10 experimenters using a better estimate of Fermi motion effects (see Tables 11-19 of this record).

The cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ integrated over each $\sqrt{\tau}$-$x_F$ cell as a function of $x_F$ for $\sqrt{\tau}$ = 0.39-0.42. The $\Upsilon$ region has been excluded. The integrated luminosity is $L = (8.58 \pm 0.53)\times 10^{37}$ [cm$^2$/W nucleus]$^{-1}$. Note that these data have been re-analysed by the NA10 experimenters using a better estimate of Fermi motion effects (see Tables 11-19 of this record).

The cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ integrated over each $\sqrt{\tau}$-$x_F$ cell as a function of $x_F$ for $\sqrt{\tau}$ = 0.54-0.60. The $\Upsilon$ region has been excluded. The integrated luminosity is $L = (8.58 \pm 0.53)\times 10^{37}$ [cm$^2$/W nucleus]$^{-1}$. Note that these data have been re-analysed by the NA10 experimenters using a better estimate of Fermi motion effects (see Tables 11-19 of this record).

The cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ integrated over each $\sqrt{\tau}$-$x_F$ cell as a function of $x_F$ for $\sqrt{\tau}$ = 0.60-0.66. The $\Upsilon$ region has been excluded. The integrated luminosity is $L = (8.58 \pm 0.53)\times 10^{37}$ [cm$^2$/W nucleus]$^{-1}$. Note that these data have been re-analysed by the NA10 experimenters using a better estimate of Fermi motion effects (see Tables 11-19 of this record).

The cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ integrated over each $\sqrt{\tau}$-$x_F$ cell as a function of $x_F$ for $\sqrt{\tau}$ = 0.66-0.72. The $\Upsilon$ region has been excluded. The integrated luminosity is $L = (8.58 \pm 0.53)\times 10^{37}$ [cm$^2$/W nucleus]$^{-1}$. Note that these data have been re-analysed by the NA10 experimenters using a better estimate of Fermi motion effects (see Tables 11-19 of this record).

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.21-0.24 interval for muon pair production in 194 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. Note that the numbers given here are different from the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>) and are a result of a re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects. See, for example, Freudenreich, <a href="https://doi.org/10.1142/S0217751X90001586">Int.J.Mod.Phys. A19 (1990) 3643</a>.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.24-0.27 interval for muon pair production in 194 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. Note that the numbers given here are different from the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>) and are a result of a re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects. See, for example, Freudenreich, <a href="https://doi.org/10.1142/S0217751X90001586">Int.J.Mod.Phys. A19 (1990) 3643</a>.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.27-0.30 interval for muon pair production in 194 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. Note that the numbers given here are different from the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>) and are a result of a re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects. See, for example, Freudenreich, <a href="https://doi.org/10.1142/S0217751X90001586">Int.J.Mod.Phys. A19 (1990) 3643</a>.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.30-0.33 interval for muon pair production in 194 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. Note that the numbers given here are different from the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>) and are a result of a re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects. See, for example, Freudenreich, <a href="https://doi.org/10.1142/S0217751X90001586">Int.J.Mod.Phys. A19 (1990) 3643</a>.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.33-0.36 interval for muon pair production in 194 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. Note that the numbers given here are different from the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>) and are a result of a re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects. See, for example, Freudenreich, <a href="https://doi.org/10.1142/S0217751X90001586">Int.J.Mod.Phys. A19 (1990) 3643</a>.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.36-0.39 interval for muon pair production in 194 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. Note that the numbers given here are different from the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>) and are a result of a re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects. See, for example, Freudenreich, <a href="https://doi.org/10.1142/S0217751X90001586">Int.J.Mod.Phys. A19 (1990) 3643</a>.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.39-0.42 interval for muon pair production in 194 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. Note that the numbers given here are different from the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>) and are a result of a re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects. See, for example, Freudenreich, <a href="https://doi.org/10.1142/S0217751X90001586">Int.J.Mod.Phys. A19 (1990) 3643</a>.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.54-0.63 interval for muon pair production in 194 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. Note that the numbers given here are different from the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>) and are a result of a re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects. See, for example, Freudenreich, <a href="https://doi.org/10.1142/S0217751X90001586">Int.J.Mod.Phys. A19 (1990) 3643</a>.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.63-0.72 interval for muon pair production in 194 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. Note that the numbers given here are different from the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>) and are a result of a re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects. See, for example, Freudenreich, <a href="https://doi.org/10.1142/S0217751X90001586">Int.J.Mod.Phys. A19 (1990) 3643</a>.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.18-0.21 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.21-0.24 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.24-0.27 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.27-0.30 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.30-0.33 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.33-0.36 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.45-0.48 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.48-0.51 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.51-0.54 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.54-0.63 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.

The differential cross section ${\rm d}^2\sigma/{\rm d}\sqrt{\tau}{\rm d}x$ as a function of $x$ in the $\sqrt{\tau}$ = 0.63-0.72 interval for muon pair production in 286 GeV $\pi^-$-tungsten interactions as measured by the CERN-NA10 experiment. The errors quoted are statistical only and no backgrounds have been subtracted. The systematic errors are dominated by the uncertainties in the flux (4%), in the efficiencies (5%), and in the absorption cross section for W. These data complement those given at 194 GeV but did not appear in the paper (Betev et al., <a href="https://doi.org/10.1007/BF01550243">Z.Phys. C28 (1985) 9</a>). The numbers here are the result of the re-analysis by the NA10 experimenters using a better estimate of Fermi motion effects.